Laminin and type IV collagen in the human testis

Specimens of normal human testis and biopsies from testes with Sertoli-cell-only syndrome in which the seminiferous tubules had a remarkably thickened lamina propria, were investigated immunohistochemically using specific antibodies against human laminin and human type IV collagen. In the normal testis, both laminin and type IV collagen were localized to the epithelial basement membranes and the peritubular cell layers. In addition, laminin was found in the Sertoli cells. In the pathological testis, structures representing invaginations of the tubular basement membrane were positive for both laminin and type IV collagen. The presence of laminin and type IV collagen in the myoid cell layers, and laminin in the Sertoli cells from both normal and pathological testis and its indication for the secretion of these substances by the myoid and Sertoli cells is discussed.     

A study on cryptorchidism. II. Light and electron microscopic study of the seminiferous tubular wall in the testes of cryptorchid patients

Morphological changes in the wall of the seminiferous tubules in the cryptorchid testes were studied using light and electron microscopy. Seventy four unilateral and bilateral cryptorchids (aged 2 to 37 years) were selected, and biopsied specimens were stained with H-E, Azan and Weigert for light microscopic observation. Twenty eight of these specimens were also examined by electron microscopy. In the undescended testes, light microscopy showed irregularity and thickening of the wall (tunica propria), and the thickened wall strongly reacted to the Azan stain. This thickening of the tunica propria was observed to begin at puberty, but was not found in the contralateral scrotal testes of the cryptorchids or in the normal testes. The wall of the normal adult testes was well stained by the Weigert stain, suggesting the presence of elastin. In the undescended testes, however, the wall was not stained in prepubertal or pubertal patients, and even after puberty the wall was stained much less than that in the contralateral scrotal testes and the normal controls. On electron microscopic observation, various ultrastructural changes were noticed in each component of the tubular wall; basement membrane, fibrous layer and cellular layer. In the undescended testes, the lamina densa of the basement membrane consisted of one layer with a serrated outer margin throughout the pre-pubertal and pubertal periods, while after puberty the lamina densa underwent marked multiple lamella formation and increased in thickness. In the fibrous layer was already noticed in the undescended testes of 5-year-old cryptorchids. The development of myoid cells in the cellular layer during puberty was observed to be delayed. The morphological changes occurring in the seminiferous tubular wall of the cryptorchid testes were believed to be related to the impaired spermatogenesis often found in cryptorchidism.     

Leydig cell hyperplasia in cryptorchid patients: Quantitative evaluation of Leydig cells in undescended and contralateral scrotal testes

Summary Leydig cell number was evaluated quantitatively in testicular biopsies from post-pubertal cryptorchid patients and normal controls. For this quantitative evaluation we used the following method. This is based on the determination of the total number of Leydig cells, Leydig cell clusters and seminiferous tubules in the entire histologic sections of each biopsy and the determination of the following indices; mean Leydig cells per tubule, mean Leydig cell clusters per tubule and mean Leydig cells per cluster. In addition, the numbers of Sertoli cells were counted, and Leydig-Sertoli cell ratio was also determined. These indices were correlated with each other. All indices were significantly elevated not only in undescended but in contralateral scrotal testes of the cryptorchid patients in comparison to those in normal controls. Between undescended and descended scrotal testes of the same individual patients, those indices were significantly higher in the descended scrotal testes than in the undescended ones. Thus, Leydig cell hyperplasia was noted in the testes of post-pubertal cryptorchid patients, and was more prominent in the contralateral scrotal testes than in the undescended ones.     

A morphological study of the testes in patients with idiopathic male infertility--immunohistochemical analysis of collagens and laminin in human testes

In the human testis, the distribution of extracellular components, such as types I, III, IV and V collagens and laminin, was investigated immunohistochemically by light microscopy. Specimens were obtained by testicular biopsy from 40 patients with idiopathic male infertility and 14 normal adult males. In the normal testes, the basement membrane was positive for types I, III, IV and V collagens and laminin. However, the distribution patterns of these components were different. Furthermore, a reactivity for types I and III collagens was found in the interstitial connective tissue matrix. Immunoreactivity for types I and III collagens was markedly positive in the limiting membranes around the Leydig cells. In the pathological testes, all the layers of the basement membrane of both thickened and obstructed tubules were positive for types I and III collagens. On the other hand, reaction products of type IV collagen were localized in the inner layer of the basement membrane and the peritubular cell (myoid cell) layer, and those of laminin were only found in the inner layer. Type V collagen-reactivity was observed in the basement membrane of thickened tubules. Positive reactions for types IV and V collagens and laminin were seldom recognized in the obstructed tubules. In the interstitial space, the connective tissues were significantly increased as compared with normal testes, which included extracellular components that reacted for types I and III collagens. Histological findings in normal adult testes and pathological testes were compared. Quantitative analysis of mean thickness of the basement membrane (W), mean seminiferous tubular diameter (T), T/W ratio and Leydig cell index demonstrated significant differences between the two groups.(ABSTRACT TRUNCATED AT 250 WORDS)     

Quantitative and ultrastructural alterations in the lamina propria and Sertoli cells in human cryptorchid testes

A quantitative and ultrastructural study was performed on biopsies of human cryptorchid testes to investigate lesions in the lamina propria and Sertoli cells. Prepubertal cryptorchid testes (1-9 years of age) were classified into four groups: Type 1, testes with minimal lesions; Type II, testes with a moderate decrease in tubule diameter and spermatogonal number; Type III, testes with Sertoli cell hypoplasia and a marked reduction in tubule diameter and spermatogonal number; and Type IV, testes with Sertoli cell hyperplasia and a variable reduction in spermatogonal number. An increase in thickness of the lamina propria was found in Type II and III testes from 5 years of age onwards. These testes also showed a decrease in both the average number of peritubular cells per cross-sectioned tubule and in the average nuclear volume of these cells. Most of the postpubertal cryptorchid testes from 13- to 18-year-old youths presented a prepubertal pattern suggestive of delayed testicular maturation. Postpubertal testes from 19- to 27-year-old men were classified into three types: Type A testes showed complete spermatogenesis, mature Sertoli cells and no lesions in the lamina propria; Type B testes showed isolated spermatogonia, mature Sertoli cells, and a marked thickening of the lamina propria; and Type C testes showed isolated spermatogonia, hyperplasia of immature Sertoli cells, and a slightly thickened lamina propria. Maturation of the lamina propria was always associated with maturation of the Sertoli cells. Thickening of the lamina propria was associated with peritubular cell alterations consisting of decreases in the nuclear volume (average and total per testis) of peritubular cells and increases in the number of these cells per cross-sectioned tubule. The three types of adult cryptorchid testes appear to be the postpubertal transformation of Type 1 testes (Type A), Type II and Type III testes (Type B), and Type IV testes (Type C).     

Elastic fibers in tunica propria of undescended and contralateral scrotal testes from cryptorchid patients

Elastic fibers in the tunica propria of the testes from cryptorchid patients and normal fertile adults were examined by light (Weigert resorcin-fuchsin stain) and electron microscopic techniques. In the testes from normal fertile adults, elastic fibers were proved to exist in the tunica propria by light and electron microscopy, and were located in the fibrous and cellular layers of the tunica propria. In the undescended testes from the cryptorchid patients, during prepubertal and pubertal periods, elastic fibers could not be visualized in the tunica propria, but were found after puberty. The positive Weigert reaction of the tunica propria in the undescended testes from postpubertal cryptorchid patients, however, was markedly weaker than that in normal control patients, suggesting diminution of elastic fibers. This diminution of elastic fibers in the undescended testes from postpubertal cryptorchid patients was also substantiated by electron microscopy. However, in the contralateral scrotal testes, elastic fibers appeared during puberty and were observed after puberty in the same manner as in normal testes. Thus, the present study suggested retarded appearance of elastic fibers in puberty and impaired development of those fibers after puberty, in the undescended testes of cryptorchid patients.     

Expression of extracellular matrix proteins and vimentin in testes of azoospermic man： an immunohistochemical and morphometric study

AIM: To investigate the changes in the extracellular matrix protein expression and the morphology of seminiferous tubules in the testis of 88 azoospermic men. METHODS: The patients were of the following categories: (1) 22 cases of Sertoli-cell-only syndrome, (2) 20 cases of spermatogenic arrest, and (3) 46 cases with hypospermatogenesis. Testicular sections were immunohistochemically stained for fibronectin, vimentin, laminin and collagen type IV. The seminiferous tubular diameter and the connective matrix zone (CMZ, the acellular zone between the basement membrane [BM] and the peritubular cells) thickness were measured. Seminiferous tubules were typed according to the thickness of the connective matrix in the lamina propria. The predominant tubule type and the Johnsen and Silber scores were determined. RESULTS: The mean tubular diameter were 119 +/- 27, 117 +/- 20, and 140 +/- 38 microm for Groups 1, 2, and 3, respectively. Both the laminin and the type IV collagen were localized to the epithelial BM and peritubular cells. In most of the tubules, BM and peritubular cells were separated by a homogenous acellular layer, the CMZ, in which laminin, type IV collagen, fibronectin and vimentin were not present. It is perceived that the worse the testicular histology, the higher the thickness of the CMZ. CONCLUSION: In testis with no or low sperm production, the diameter of the seminiferous tubules is decreased, the thickness of the seminiferous tubular wall is increased and a CMZ is formed between the peritubular cells and the BM. The thickness of CMZ is increasing with the advancement of testiclar deterioration. The most important morphologic predictive factor for spermiogenesis is the predominant     

Postpubertal cryptorchism. Morphofunctional study with special reference to Leydig's cells

In a group of 17 patients of postpubertal age with unilateral (n = 15) or bilateral (n = 2) cryptorchism, a significant decrease in the tubular diameter was observed, in addition to Leydig cell hyperplasia (many with cytoplasm vacuolization and/or atrophy) in both the cryptorchid testes and in the contralateral scrotal testes. The number of testosterone-positive Leydig cells in testicular tissue sections, studied with peroxidase-antiperoxidase, was diminished in the cryptorchid testes, whereas in the contralateral scrotal testes it was similar to the control group. Together with normal testosterone levels and elevated luteinizing hormone and follicle-stimulating hormone levels in peripheral blood, this leads us to think of a compensated dysfunction of the Leydig cells. This possible lower testosterone production by the Leydig cells in the cryptorchid testis is not borne out morphologically, where the volume of the organelles is similar to the contralateral scrotal testes.     

Production of lactate and tissue plasminogen activator in vitro by seminiferous tubules obtained from adult unilaterally cryptorchid rats

Pieces of seminiferous tubules obtained from adult unilaterally cryptorchid rats were incubated in vitro and the effect of FSH on the secretion of lactate and tissue-plasminogen activator (t-PA) was studied. Tubules from abdominal testes secreted less lactate than scrotal tubules. On the other hand, the basal secretion of t-PA was similar but the FSH-stimulated t-PA secretion was larger from abdominal than from scrotal tubules. These results indicate a more specific dysfunction of the Sertoli cells in cryptorchidism than earlier recognized.     

A study of cryptorchidism. I. Light and electron microscopic study of Leydig's cells in the testes of cryptorchid patients

A morphological study of the Leydig's cells in the testes of cryptorchid patients was made by light and electron microscopy. Seventy four unilateral and bilateral cryptorchids (aged 2 to 37 years) were selected for light microscopic observation, and 28 of these specimens were also examined by electron microscopy. In 5 cases of pre-pubertal and pubertal cryptorchids, tissue specimens were biopsied after 20,000 units of HCG had been given and examined similarly. In addition, Leydig's cell density was evaluated quantitatively in the undescended and contralateral scrotal testes of 12 post-pubertal patients. This was based on the determination of the total number of Leydig's cells, Leydig's cell clusters and seminiferous tubules in the entire histologic section of each biopsy and the calculation of the following indices; mean number of Leydig's cells per tubule, mean number of Leydig's cell clusters per tubule and mean number of Leydig's cells per cluster. In addition, the number of Sertoli's cells was counted, and the ratio of Leydig's cells to Sertoli's cells was also calculated. In the undescended testes, almost no mature Leydig's cells were found by light or electron microscopy during pre-pubertal periods; and, even in puberty they were few, while immature precursor Leydig's cells were abundant. In the 5 cases treated preoperatively with HCG, even at 5 years, mature Leydig's cells were observed by light and electron microscopy. On the contrary, after puberty, not only the undescended but also the contralateral scrotal testes of the cryptorchids had more mature Leydig's cells than the normal controls. This Leydig's cell hyperplasia was also confirmed by the quantitative analysis of Leydig's cell density. In the mature Leydig's cells of the undescended testes, however, the electron microscopic observation showed marked regressive changes, in cytology especially prominent depletion of the smooth endoplasmic reticulum and frequent occurrence of specific cytoplasmic inclusion bodies. Such regressive changes as found in the cells of the undescended testes were not observed in the cells of the contralateral scrotal testes. Thus, the morphological alteration of Leydig's cells observed here suggest that the cells are in a dysfunctional condition and that the androgen production is consequently decreased in the undescended testes of cryptorchid patients.     

Secondary changes in the scrotal testis in experimental unilateral cryptorchidism

Unilateral cryptorchidism was induced in under 2-day-old Wistar rat pups. A control group of rats underwent sham operation at the same age. The animals were killed at intervals from 5 to 120 days, both testes were excised, weighted, and processed for histological examination, morphometric measurement of the seminiferous tubules, and DNA flow cytometry. There was no difference in weight, Johnsen score, and tubular size between the scrotal testis of cryptorchid animals and control testes at any age. Significant decreases in all of these parameters occurred in the undescended testis from 30 days when compared with the scrotal testis in cryptorchid animals and controls. Using flow cytometry to measure changes in the DNA ploidy of the cells of the seminiferous epithelium during spermatogenesis, a significant decrease in the haploid population of cells occurred in the scrotal testis of cryptorchid animals at 40 days. This difference continued into adult life (P less than .005). Flow cytometry demonstrates a secondary decrease in spermatogenesis in the scrotal testis in experimental unilateral cryptorchidism.     

Immunohistochemical study of glutathione S-transferase in normal and experimental cryptorchid testes rats]

Using the antibody for glutathione S-transferase (GST) purified from human kidney, normal testes and experimental cryptorchid testes from newborn to 20-week-old rats were immunohistochemically stained by the peroxidase antiperoxidase (PAP) method. The cryptorchidism was surgically created at 1 week of age. The localization of GST was particularly examined by light microscopy, and the amount of Leydig cells was measured by a stereological method. 1. Leydig cells in the normal and cryptorchid testes showed strong GST activity at all ages. The amount of these cells in normal testes increased from 4 to 8 weeks of age and then slightly decreased, whereas in cryptorchid testes it was significantly larger than in the normal testes at 20 weeks of age, indicating hyperplasia of Leydig cells. 2. In the normal and cryptorchid testes, degenerating primary spermatocytes with GST activity appeared in the seminiferous tubules at 2 to 4 weeks of age. In the cryptorchid testis, degenerating germ cells with GST activity were also found in the regressing seminiferous tubules after 4 weeks of age. It is possible that GST acts as a detoxification system in the degenerating germ cells. 3. The PAP staining of GST in the rat testes is considered to be useful method for evaluating metabolic function of the spermatogenic cells and the distribution and amount of Leydig cells. 4. Experimental cryptorchidism showed that germ cells become sensitive after 4 weeks of age.     

Ischemia,whether from ligation or torsion,causes ultrastructural changes on the contralateral testis

OBJECTIVE: Unilateral testicular torsion results with a decrease in contralateral testicular blood flow caused by a reflexive sympathetic response. The aim of this study was to investigate whether twisting of the spermatic cord, or testicular ischemia without twisting, activates this reflex mechanism and causes ultrastructural changes in the contralateral side. MATERIALS AND METHODS: Thirty adult male albino Wistar rats were randomly allocated into three groups of sham, torsion, and ligation. Right testes were twisted 720 degrees counterclockwise in the torsion group. Right spermatic cords were ligated permanently with a silk suture including the vas deferens in the ligation group. After 24 h of testicular ischemia, contralateral left testes were removed for electron microscopic evaluation. RESULTS: Contralateral testes showed similar ultrastructural changes in the torsion and ligation groups. The fibrous tunica propria enveloping the seminiferous tubule was thickened due to increased collagen fibers. The basal lamina was continuous but thickened and showed several foldings. The gap between basal lamina and the germ cells was increased because of collagen fibers. Leydig cells showed mitochondrial degeneration with the loss of its cristae. Leydig cells lost their contact with its neighborhood cells in some areas, and these gaps were filled with collagen fibers. Germ cells showed dilated cisternae of smooth endoplasmic reticulum, cytoplasmic electron-dense bodies and clear regions. CONCLUSIONS: Similar electron microscopic findings observed in the torsion and ligation groups indicate that testicular ischemia rather than twisting of the spermatic cord is responsible for the ultrastructural changes in the contralateral side.     

Changes in the volume and histology of retractile testes in prepubertal boys

Testicular development was studied in prepubertal boys with retractile testes. Testicular volume, the diameter of the seminiferous tubules and the number of spermatogonia in the tubules were decreased in cases of unilateral retractile testis, when compared with values for the contralateral normally descended testis. On the other hand, in patients with a unilateral retractile testis and contralateral inguinal testis, there was no difference in the developmental parameters between the two testes. These results suggest that the retractile testis has developmental failures characteristic of a cryptorchid testis and therefore requires orchiopexy.     

Stagnation of blood in the microvasculature of the affected and contralateral testes of men with short-term torsion of the spermatic cord

Bilateral testicular biopsies from four men with a short duration (3 hours 10 minutes to 4 hours 30 minutes) of unilateral spermatic cord torsion and testicular biopsies from six men with irreversible brain death were used for the present investigation. Extensive light and electron microscopic studies and quantitative analyses of all biopsy materials were performed. The torsioned testes revealed variable degrees of damage to the seminiferous tubules, including germ cell disorganization and sloughing of immature germ cells. Ninety-five percent of the blood vessels from the biopsied tissue specimens were clogged with blood cells. The seminiferous tubules of the contralateral testis had normal germ cell arrangements and counts. However, 88% of the microvessels from the tissue biopsied from the contralateral testes were packed with blood cells, whereas only 10% of the blood vessels in the control biopsy specimen were clogged with blood cells. At the electron microscopic level, fewer tight junctions and enlarged pores were found between the endothelial cells of the affected vessels, and microvilli were completely absent from these endothelial cells. The clogging caused by blood cells in the affected vessels was so severe that no space was found between the membrane of the endothelial cell and the membrane of the blood cells. It has been suggested that local clogging by blood is responsible for the initiation of degenerative changes in the testes of men with unilateral torsion of the spermatic cord.     

双侧短期隐睾大鼠睾丸形态及抑制素的研究

本文研究了双侧短期人为隐睾大鼠睾丸的形态及抑制素的变化。结果发现隐睾一周和四周的大鼠睾丸和付睾重量均减轻。曲细精管直径缩小(平均直径:对照组250μm±43.75μm,1周组,159.5±32.25;4周组139.25±22.5;与对照组比P均<0.01)。Leydig细胞切面面积比明显增大(对照组为(％)6±2.4,1周组为21.83±7.4,4周组为23±11.38,P均<0.01)。电镜发现隐睾组leydig氏细胞线粒体和内浆网数量均增多,局部呈囊性扩张。睾丸间液和血清抑制素含量均明显下降(与对照组比P分別<0.01和<0.05),表明曲细精管破坏与leydig细胞呈一定的负相关。支持精管控制leydig氏细胞的理论,是否抑制素参于这一过程有待证实。     

Investigations of arterio-venous anastomoses in the spermatic cords and blood supply, oxygen consumption and testosterone production of scrotal and abdominal testes in the pig

This study has investigated blood flow from the testicular artery to the pampiniform plexus in the spermatic cord of pigs. Testosterone levels, oxygen tension and the degree of acidity were measured in arterial and venous blood vessels of scrotally and abdominally located testes. Haemoglobin oxygen saturation was derived from the oxygen dissociation curve. Blood flow to abdominal and scrotal testes and epididymides was measured using the radioactive microsphere technique. Average blood flow to the scrotal testes and epididymides was 21 and 8 ml/min, respectively, in normal pigs. In unilaterally cryptorchid pigs average blood flow to the scrotal testis and epididymis was 23 and 6 ml/min, respectively, and to the abdominal testis and epididymis 4.2 and 1 ml/min. In pigs with bilateral scrotal testes oxygen consumption was 16 mumol O2/min/100 g. In unilaterally cryptorchid pigs oxygen consumption by the scrotal testis was 18 mumol O2/min/100 g, compared with 10 mumol O2/min/100 g by cryptorchid testes. From the percentage oxygen saturation in the various blood vessels it was calculated that 29-42% of testicular arterial blood was flowing through arteriovenous anastomoses between the testicular artery and the pampiniform plexus in the spermatic cord, thus bypassing the capillary net of the abdominal testes of unilaterally and bilaterally cryptorchid pigs. These results were supported by the testosterone measurements. In the spermatic cord of scrotal testes no blood bypassed the capillary net of the testes.     

Steroid metabolism and morphologic features of the human testis

Serum FSH, LH, and testosterone were studied in 114 infertile men with poor sperm production. Testicular biopsies were taken and classified morphologically. In 90 specimens, the pattern of conversion of progesterone was determined in vitro and expressed as the ratio of 20 alpha-hydroxy-4-pregnene-3-one to 17 alpha-hydroxyprogesterone. An excess of the former metabolite indicates a prepubertal type of steroid metabolism. The normal limit of this ratio is given. The collected data indicate that the prepubertal type of steroid metabolic pattern is related to the thickness of the lamina propria of the seminiferous tubules only, and not to peripheral hormone levels. In particular, the presence of hyaline deposits in the lamina propria seems to determine the metabolic pattern. It is suggested that the character of the lamina propria separating the tubular and interstitial compartments of the testis is of crucial importance for the functional interrelationship between these compartments. This supports the concept of an intratesticular regulatory mechanism of both steroid metabolism and spermatogenesis.     

The time-response and magnitude of HCG-induced vascular changes are different in scrotal and abdominal testes

Adult unilaterally cryptorchid rats were injected with 50 IU human chorionic gonadotrophin (hCG). At 4, 8, 24 and 72 h after treatment, testicular vascular permeability was studied by injecting colloidal carbon intravenously. The number of blood vessel profiles labelled with carbon was increased by hCG in both types of testes, but the response was more sustained in abdominal than in scrotal testes. The number of polymorphonuclear leucocytes (PMNs) accumulating in testicular blood vessels and migrating into the interstitial space in response to hCG treatment was also measured. The volume density of intravascular and interstitial PMNs was increased in both types of testes but the peak response was larger in scrotal than in abdominal testes. PMN accumulation and vascular leakage were apparently correlated in the scrotal but not in the abdominal testes.
Testicular interstitial fluid (IF) was collected from intact and unilaterally cryptorchid adult rats. The IF was diluted with sterile buffer and injected intracutaneously in test animals. The vascular permeability response was assessed by measuring the leakage of Evans blue into the injection sites. IF from scrotal and abdominal testes increased vascular permeability in the skin. The response was rapid and transient. IF collected from rats given hCG 24 h earlier did not increase vascular permeability. The vascular permeability response to IF was reduced slightly in neutrophil-depleted animals. The inflammation mediator present in IF cannot explain the kinetics and magnitude of the hCG-induced changes in vascular premeability in intact or unilaterally cryptorchid rats.     

Mechanism of alcoholic testicular damage]

To observe the mechanism of alcoholic testicular damage, in a previous experiment we used weanling male SD rats aged 45 days, weighing about 200 g, and fed a liquid diet (Lieber's) containing 5% ethanol. The latter accounted for 36% of total caloric intake for 7 weeks, but did not result in testicular atrophy. In a later experiment, we used a liquid diet in which ethanol accounted for 46% of the total calorie count. It provided a high-fat, low-protein content which simulated the nutritional background of patients with alcoholic liver diseases. This diet resulted in testicular atrophy. Histological and biochemical changes accompanying this experimental testicular atrophy included the following: 1) The testes of alcohol-fed animals contained smaller seminiferous tubules with reduced numbers of total cells, but no degeneration was seen in the spermatids. 2) In the peritubular wall of the seminiferous tubules, we observed curvature, irregularities, infolding of the basement membrane, and lamellation of the lamina densa, as well as hyperplasia of collagen fibers in the tunica propria. 3) In the cytoplasm of the Sertoli cells, deposits of gigantic fat droplets and stratification of the mitochondria were observed. The permeability of the Sertoli cell tight junction was confirmed using the Lanthanum method. 4) Testosterone levels in both the serum and testes declined. 5) Lactate dehydrogenase-X (LDH-X) activity in the testes declined. 6) Low Km alcohol dehydrogenase (ADH) activity localized in the testicular interstitial tissue was increased. These results indicate that the composition of three major nutritional elements as well as alcohol concentration are important in the mechanism of alcoholic testicular damage, and this damage affects both the testicular interstitial cell and the seminiferous tubules, particularly the Sertoli cells and peritubular wall of the latter. In addition, the findings suggest that ADH is involved in alcohol metabolism in the interstitial cells of the testes.