Ontogeny and immunocytochemical differentiation of the pituitary gland in a sea turtle, Caretta caretta

In the sea turtle Caretta caretta the dorsal wall of the pituitary anlage and the apex of the hypophyseal angle are derived from stomodeal epithelium adherent to the neural epithelium of the diencephalon; a substantial part of the ventral wall of the anlage is derived from epithelium of mixed origin (stomodeum and foregut). Distribution of immunoreactive cells in the embryonic gland suggests that pituitary peptide hormones (adrenocorticotropin, ACTH; melanotropin, MSH; prolactin, PRL; growth hormone, GH) are synthesized in cells from the dorsal wall, while cells producing glycoprotein hormones (luteinizing hormone, LH; thyrotropin, TSH) trace their lineage to ventral and ventrolateral areas of the anlage that include some endoderm. Mesenchymal movements mold the epithelial anlage in two steps, delineating first the posterior and subsequently the anterior area of the gland. During the former process the lateral lobes are defined, and material immunoreactive with antiserum to ACTH appears in epithelial cells of presumptive pars distalis (PD) and pars intermedia (PI). Delineation of the anterior end of the pituitary gland occurs as the hypophyseal stalk forms, approximately one-fourth through ontogenesis. Shortly thereafter, immunoreactions demonstrate synthetic activity of distinctively distributed cells containing ACTH, PRL, GH, LH and TSH. In Caretta the lateral lobes of the pituitary anlage give rise to a distinct layer of tissue around the PD (pars tuberalis interna, PTint) and a thick layer on the floor of the hypothalamus (juxtaneural pars tuberalis, juxPT). In the pituitaries of late embryos, juxPT tissue proximal to the PD contains many cells immunoreactive with LH antiserum; whereas cells in distal areas of the juxPT do not react with any antisera tested. LH-cells also occur in large numbers in the PTint and in the posterior PD where tissues of the partes tuberalis and distalis are continuous. Cells reactive with antiserum to TSH are found in small numbers in the PTint, and in larger numbers along with the LH-cells in the posterior PD. PRL-cells occur in the anterior PD, GH-cells in the posterior. ACTH-cells are found primarily in the anterior two-thirds of the PD.     

Chronological study of the appearance of adenohypophysial cells in the ayu (Plecoglossus altivelis)

We previously reported the chronological appearance of adenohypophysial cells in freshwater teleosts using an immunocytochemical technique. The present study investigated the chronological appearance of adenohypophysial cells in the ayu, which is spawned and has its early development in brackish water, and the results were compared with those obtained in freshwater and seawater teleosts, as well as in other vertebrates. In the adult teleostean adenohypophysis, seven or eight types of secretory cells have been distinguished, each of which produce different hormones: prolactin (PRL), growth hormone (GH), thyroid stimulating hormone (TSH), gonadotropic hormones (GTH I and GTH II), adrenocorticotropic hormone (ACTH), melanophore stimulating hormone (MSH) and somatolactin (SL). In the pituitary of adult ayu, seven distinct types of glandular cells (PRL, GH, TSH, GTH, ACTH, MSH and SL cells) were identified. Chronologically, a few immunoreactive (ir)-PRL and ir-GH cells appeared in the ventral side of the pituitary one day before hatching. Then, just after hatching, ir-GTH cells were observed in the central to dorsal portion; ir-ACTH cells were found distributed in the anterior portion and some ir-MSH and a few ir-SL cells were seen in the posterior portion of the pituitary. Finally, a small number of ir-TSH cells were identified 50 days after hatching. These results differed from those obtained in other fishes previously reported with regard to the times of appearance of the PRL and GH cells. PRL cells appeared first, followed by GH cells in the freshwater teleosts, PRL and GH cells appeared at the same time in the brackishwater teleosts, while GH cells appeared first and PRL cells appeared last in the seawater teleosts. These results reflect the fact that PRL plays a major role in osmoregulation among freshwater teleosts, as compared with GH, which plays a similar role in seawater teleosts. It seems that both PRL and GH may play important roles in osmoregulation in brackishwater fish.     

Chronological study of the appearance of adenohypophysial cells in the ayu ( Plecoglossus altivelis )

We previously reported the chronological appearance of adenohypophysial cells in freshwater teleosts using an immunocytochemical technique. The present study investigated the chronological appearance of adenohypophysial cells in the ayu, which is spawned and has its early development in brackish water, and the results were compared with those obtained in freshwater and seawater teleosts, as well as in other vertebrates. In the adult teleostean adenohypophysis, seven or eight types of secretory cells have been distinguished, each of which produce different hormones: prolactin (PRL), growth hormone (GH), thyroid stimulating hormone (TSH), gonadotropic hormones (GTH I and GTH II), adrenocorticotropic hormone (ACTH), melanophore stimulating hormone (MSH) and somatolactin (SL). In the pituitary of adult ayu, seven distinct types of glandular cells (PRL, GH, TSH, GTH, ACTH, MSH and SL cells) were identified. Chronologically, a few immunoreactive (ir)-PRL and ir-GH cells appeared in the ventral side of the pituitary one day before hatching. Then, just after hatching, ir-GTH cells were observed in the central to dorsal portion; ir-ACTH cells were found distributed in the anterior portion and some ir-MSH and a few ir-SL cells were seen in the posterior portion of the pituitary. Finally, a small number of ir-TSH cells were identified 50 days after hatching. These results differed from those obtained in other fishes previously reported with regard to the times of appearance of the PRL and GH cells. PRL cells appeared first, followed by GH cells in the freshwater teleosts, PRL and GH cells appeared at the same time in the brackishwater teleosts, while GH cells appeared first and PRL cells appeared last in the seawater teleosts. These results reflect the fact that PRL plays a major role in osmoregulation among freshwater teleosts, as compared with GH, which plays a similar role in seawater teleosts. It seems that both PRL and GH may play important roles in osmoregulation in brackishwater fish. Accepted: 18 May 1999     

三叶因子3在大鼠腺垂体嗜色细胞中的定位

目的探讨三叶因子3(TFF3)在腺垂体远侧部嗜酸性细胞和嗜碱性细胞中的表达,明确TFF3在远侧部的分布。方法采用相邻切片的免疫组织化学染色,在相邻切片上分别显示TFF3/生长激素(GH)、TFF3/催乳素(PRL)、TFF3/促甲状腺激素(TSH)、TFF3/促肾上腺皮质激素(ACTH)、TFF3/卵泡刺激素(FSH)、TFF3/黄体生成素(LH)的表达。结果 TFF3和各嗜色细胞的免疫反应产物为棕黄色,主要位于细胞质,ACTH免疫阳性信号在胞膜也有表达,主要分布在腺垂体的远侧部。邻片显示TFF3存在于部分GH、PRL、TSH、ACTH、FSH、LH细胞,分别占19.4%、22.4%、9.2%、6.5%、35.7%、8.3%,以FSH最多,PRL、GH次之。结论垂体远侧部TFF3可分别表达于GH、PRL、TSH、ACTH、FSH、LH细胞。     

Identification of mammosomatotropes, growth hormone cells and prolactin cells in the pituitary gland of the gilthead sea bream (Sparus aurata L., Teleostei) using light immunocytochemical methods: an ontogenetic study

Growth hormone (GH) and prolactin (PRL) immunoreactivities in the adenohypophysis of Sparus aurata specimens from newly hatched until 48-months-old were detected using the peroxidase-antiperoxidase method. GH cells and PRL cells, and cells that were immunoreactive to both GH and PRL antisera, called mammosomatotropes (MS cells), were found. This is the first report on the identification of MS cells in fish, which were found in newly hatched and older larvae and juvenile specimens. GH and PRL cells appeared from two days after hatching. MS cells were first located in the central region of the adenohypophysis and afterwards in the rostral pars distalis. The GH cells were first identified in the dorsal and ventral areas of the middle-posterior part, and the PRL cells in the ventral region of the middle-anterior part. Later, during development, the sequence of appearance of the GH cells was proximal pars distalis, pars intermedia and rostral pars distalis, while for the PRL cells sequence was rostral pars distalis, proximal pars distalis and pars intermedia. This expansion pattern could be due to a GH- and PRL-cell migration although independent cell differentiation may occur in each region. The present results suggest that GH and PRL cells arise from MS cells at the outset of pituitary development, while MS cells procede from PRL cells in old larvae and juveniles. Accepted: 8 June 2000     

Identification of prolactin and growth hormone cells in the pars distalis of the California leaf-nosed bat,Macrotus californicus

Prolactin (PRL) and growth hormone (GH) cells were immunostained in the anterior pituitary lobe of the California leaf-nosed bat with antisera against rat PRL and GH by the unlabeled immunoperoxidase technique. The PRL antiserum reacts with a cell that is carmoisinophilic and pleomorphic and occurs in small groups within the ventro-, dorsocentral, and posteriolateral regions of the pars distalis. The cells that stain with the anti-GH serum are orangeophilic, smaller than the PRL cells, and randomly scattered throughout the pars distalis, singly or in palisades near capillaries. Morphometric analysis of the immunoreactive PRL and GH cells revealed an inverse relationship between these two cell types.     

Immunohistochemical study on the development of the adenohypophysial cells in the lizard Gallotia galloti

Summary Immunohistochemical methods have been used to study the embryonic and postnatal development of the hormone-producing cells in the adenohypophysis of the lizard Gallotia galloti. In this species, Rathke's pouch is formed between stages 30 to 32 of the embryonic development, although the first sign of immunoreactivity to antisera against adenohypophysial hormones occurs in stage 33 in the pars distalis anlage. These cells derive from the dorsal face of Rathke's pouch and are immunoreactive to anti-ACTH serum. The cytodifferentiation of ACTH and MSH cells occurs in the pars intermedia in stage 34. The TSH cells appear at stage 35 and the gonadotrope cells at stage 37. These cells derive from both the dorsal and ventral face of the Rathke's pouch. The LTH cells are revealed at stage 39 and are only originated from the dorsal face. The STH cells, which come from the dorsal as well as ventral face, are the last secretory cells differentiated just before hatching. During postnatal development an increase and also a redistribution of the immunoreactive cells occur until acquiring the adult distribution.     

Immunocytochemistry of ambiguous cells in adult and embryonic dwarf (dw) mouse pituitaries

In the pars distalis of the pituitary gland in adult and embryonic dwarf (dw/dw) mutant mice, ambiguous cells exhibiting ultrastructural features common to growth hormone (GH) cells and prolactin (Prl) cells were analyzed by means of colloidal gold ultrastructural immunocytochemistry in order to define the functional nature of these peculiar cells. Adult and 18-day embryonic pituitaries from normal (+/+; dw/+) and dwarf (dw/dw) mice were processed with antibodies to GH, Prl, TSH (thyroid-stimulating hormone), ACTH (adrenocorticotropic hormone), LH (luteinizing hormone), FSH (follicle-stimulating hormone), and HCG (chorionic gonadotropic hormone). In the adult and embryonic dwarf pituitaries, the ambiguous cells reacted negatively to all of the antibodies except for anti-ACTH, which labeled them well. In addition, the ACTH-positive cells showed a much wider variety of shapes and granule size and distribution, as compared with normal adults. In the embryos, this variability in ACTH cell morphology occurred not only in dwarf embryos, but in their normal counterparts as well. The results thus suggest that adult dwarf pituitaries may retain an embryonic or incompletely differentiated form of ACTH cells. © 1993 Wiley-Liss, Inc.     

Cellular composition of the rostral pars distalis of the anterior pituitary gland of the alewife, Alosa pseudoharengus, during the spawning run

The rostral pars distalis of the anterior pituitary gland of the marine alewife, Alosa pseudoharengus, during its annual spawning run to fresh water was examined histologically. The rostral pars distalis is composed of many interconnecting follicles of various sizes. Contrary to earlier reports, the follicular epithelium contains not only prolactin (PRL) cells but corticotropic (ACTH) cell and thyrotropic (TSH) cells (in addition to two nonendocrine cell types). Basally all three endocrine cell types make direct contact with the basement membrane which separates the follicles from the neurohypophysial processes. Apically, however, only the prolactin cells, the largest of the three, protrude into the follicular lumen by means of the small ciliated apical protruberance. All other cellular elements are sealed from the follicular lumen by a layer of covering cells which have properties of transitional epithelial cells. In the follicular epithelium, the slender TSH cells are intercalated between the large conspicuous prolactin cells. The ACTH cells, the smallest of the three endocrine cells, lie in deep invaginations in the basal regions of the individual PRL cells in such a way that on cursory examination they can be mistaken for the nuclei of the latter. Only a small portion of the cellular surface of the ACTH cell escapes the enveloping prolactin cell to make contact with the basement membrane of the follicle. In teleosts, prolactin, ACTH, and TSH have all been implicated in the regulation of hydromineral metabolism and reproductive development. The intimate spatial relation between the three endocrine cells in the alewife rostral pars distalis thus raises the possibility of some functional interactions at the adenohypophysial level, perhaps as an adaptation of this anadromous teleost whose reproductive development and behavior is associated with large changes in ambient salinity. The functional significance of the follicular lumen is discussed together with possible sensory functions of the PRL cells.     

Immunohistological localization of TGFα, EGF,IGF-I,and TGFβ in the normal human pituitary gland

In previous studies, we demonstrated several growth factors, including epidermal growth factor (EGF), transforming growth factorβ (TGFβ), insulin-like growth factor-I (IGF-I, somatomedin C), and TGFe in extracts of the human pituitary. Using immunohistochemistry, reactivity for TGFα, EGF, and TGFβ was localized in sections of 12 of 12 autopsy-derived human pituitary glands. IGF-I reactivity was demonstrated in 5 of 5 pituitary glands. Sections staining for TGFα and IGF-I were double-stained for the full spectrum of anterior pituitary hormones (i.e., GH, PRL, ACTH, LH, FSH, TSH, and a-subunit). Intracellular EGF immunostaining was demonstrated within the posterior pituitary and in some squamous cell nests of the pars tuberalis. Occasional extracellular EGF reactivity was also noted within connective tissue of the anterior pituitary. Polyclonal antibody to TGFβ showed extracellular reactivity within connective tissue surrounding the gland as well as that separating cords of secretory cells. TGFβ staining was also noted in the mediae of small vessels. Monoclonal anti-TGFα antibody labeled scattered secretory cells throughout the anterior pituitary, including ones engaged in follicle formation, and some cells lining Rathke’s cleft remnants. TGFα reactivity in secretory cells was expressed in cells also staining for PRL, α-subunit, LH, FSH, and TSH. No TGFα reactivity was noticed in cells staining for either GH or ACTH. IGF-I reactivity was observed in occasional secretory cells within the anterior pituitary and in neuronal processes of the posterior pituitary. Anterior pituitary cells reactive for hormones were nonreactive for IGF-I. The presence of EGF and TGFβ reactivity within extracellular matrix suggests that it represents a possible storage site of these growth factors within the anterior pituitary. The presence of EGF and IGF-I within the axons and terminations of posterior pituitary implies either local or possibly hypothalamic production of EGF. Finally, our results indicate that TGFα and IGF-I, as well as perhaps EGF, are manufactured by specific pituitary cells and that they may have a role in the endocrine function of the anterior and posterior pituitary, respectively.     

Role of adenohypophyseal mixed cell-follicles in age estimation

In this study we used paraffin-embedded human pituitary obtained from 248 autopsy cases and identified mixed cell follicles by the immunohistochemical method. We examined the number and size of the mixed cell follicles, and the ratio of each component cell of these follicles, in the anterior pituitary at various age groups. The number of follicles increased with age, and the size of the follicles also tended to enlarge with age. Statistical analysis showed that a high correlation existed between age and the number or the size of the mixed cell-follicles formed by various adenohypophyseal cells. In addition, when the proportions of the different cell types that formed the follicles were examined, sex differences were observed with aging for the GH cells, the PRL cells, and the gonadotroph (GTH) cells, while no changes were observed with aging in both men and women for the ACTH cells and TSH cells. These results indicate that the number, size, and ratio of each component cell of follicles in the anterior pituitary are adequately applicable for the purpose of age estimation in routine forensic medicine.     

Pituitary adenomas of the multiple endocrine neoplasia type I syndrome

In a series of 1,500 pituitary adenomas surgically resected at Mayo Clinic, 41 (2.7%) occurred in the setting of multiple endocrine neoplasia, type I (MEN-I). Of the 40 patients (18 males, 22 females), 21 (52%) presented with clinical evidence of a pituitary neoplasm, 13 with hyperparathyroidism, and two with functional islet cell tumor. Of the 41 tumors, 11 (27%) were microadenomas, and 30 (73%) were macroadenomas. Immunocytochemical studies demonstrated the following reactivities: GH (4), GH/PRL (6), GH/PRL/glycoprotein (7), GH/ACTH/glycoprotein (1), PRL (16), PRL/TSH (1), ACTH (3), and null cell adenoma (3). We conclude that, in comparison with pituitary adenomas occurring in the general population, those occurring in association with MEN-I are (1) more often endocrinologically functional, (2) more frequently GH- or PRL-producing, and (3) clinicopathologically similar in terms of the subjects age and sex as well as of tumor size and invasiveness.     

Immunohistological analysis in the distribution of cells in the fetal porcine adenohypophysis.

Adenohypophyses of porcine fetuses from 25 to 110 days of gestation were studied by immunohistochemical staining to ascertain the ontogeny of specific cell types and their spatial distribution in the pars distalis. No hormone-containing cells were found before 30 days of gestation. ACTH cells were observed first at 40 days, while GH and LH cells appeared first at 60 days. PRL cells were initially detected at 105 days. ACTH immunoreactive cells were also observed in the pars intermedia at 40 days. Blood capillaries were interposed between cell cords of the pars distalis after 40 days of gestation. ACTH cells were evenly distribution in all areas of the pars distalis except the rostral area (sex zone). GH cells were densely distributed in lateral wings of the pars distalis and immediately anterior to Rathke's lumen. PRL cells resembled GH cells in their distribution pattern, but PRL cells were fewer in number. LH cells were scattered in the sex zone of the pars distalis from 60 to 80 days of gestation. After 90 days, they became scattered throughout the pars distalis but were more numerous in the sex zone than in other areas. The inductive elements of adenohypophysial cells from Rathke's pouch epithelia are discussed. We hypothesize that cell cords of specific areas facing Rathke's lumen may differentiate into specific cell types of the pars distalis during fetal life.     

Immunohistological analysis in the distribution of cells in the fetal porcine adenohypophysis

Adenohypophyses of porcine fetuses from 25 to 110 days of gestation were studied by immunohistochemical staining to ascertain the ontogeny of specific cell types and their spatial distribution in the pars distalis. No hormonecontaining cells were found before 30 days of gestation. ACTH cells were observed first at 40 days, while GH and LH cells appeared first at 60 days. PRL cells were initially detected at 105 days. ACTH immunoreactive cells were also observed in the pars intermedia at 40 days. Blood capillaries were interposed between cell cords of the pars distalis after 40 days of gestation. ACTH cells were evenly distribution in all areas of the pars distalis except the rostal area (sex zone). GH cells were densely distributed in lateral wings of the pars distalis and immediately anterior to Rathke's lumen. PRL cells resembled GH cells in their distribution pattern, but PRL cells were fewer in number. LH cells were scattered in the sex zone of the pars distalis from 60 to 80 days of gestation. After 90 days, they became scattered throughout the pars distalis but were more numerous in the sex zone than in other areas. The inductive elements of adenohypophysial cells from Rathke's pouch epithelia are discussed. We hypothesize that cell cords of specific areas facing Rathke's lumen may differentiate into specific cell types of the pars distalis during fetal life. © 1992 Wiley-Liss, Inc.     

吗啡依赖及戒断后大鼠垂体远侧部促肾上腺皮质激素细胞和甲状腺刺激激素细胞组织学研究

目的:观察吗啡依赖大鼠及戒断大鼠垂体远侧部促肾上腺皮质激素(ACTH)细胞和甲状腺刺激激素(TSH)细胞的变化。方法:皮下规律注射吗啡建立大鼠吗啡依赖模型,戒断后造成戒断模型并用免疫组织化学和图像分析方法检测吗啡依赖及戒断后大鼠垂体远侧部ACTH细胞和TSH细胞的变化。结果: 吗啡依赖大鼠ACTH细胞和TSH细胞免疫反应减弱(P＜0.01),短期戒断后这些改变仍持续存在。 结论:吗啡可导致大鼠脑垂体分泌功能紊乱,且短期戒断后未能完全恢复。     

Three-dimensional distribution patterns of PRL,GH and ACTH cells in the house musk shrew ( Suncus murinus)

Despite a multitude of reports on the classification and distribution of anterior pituitary cells, no previous study has attempted to obtain the three-dimensional (3D) and computer-graphic distribution pattern of each cell type in the whole pituitary. Therefore, we mapped the anterior pituitary cells of the house musk shrew ( Suncus murinus) and found a distinct cellular distribution pattern. Serial horizontal sections of whole shrew pituitaries were stained immunohistochemically for prolactin (PRL), growth hormone (GH), and adrenocorticotropic hormone (ACTH) cells. The contours of positive cells and the anterior, intermediate, and posterior lobes in each section were digitized for 3D visualization by a volume rendering method. The reconstructed images and virtual frontal and sagittal slices were examined in detail. On the 3D reconstructed images, the PRL and GH cells had similar distribution patterns, although the former were concentrated in the dorsolateral and ventrocentral portions, and the latter in the dorsocentral portions of the anterior lobe. On both sides of the pituitary stalk, there lay portions that were conspicuous by scarcity of PRL and GH cells. ACTH cells were widely scattered throughout the whole anterior lobe, but they were very few in the above portions and the dorsocentral portions where GH cells were concentrated. No sex difference in the distribution patterns of each cell type was observed. However, PRL cells in females were more numerous than in males, whereas the opposite was true for GH and ACTH cells. We discuss the relationship between the formation of the spatial distribution patterns and anterior pituitary ontogeny.     

Immunohistochemical studies on the development of the hypothalamo-hyophysial system in Xenopus laevis

Background: Few attempts have bee made to clarify the relational development of the hypothalamo-adenohypophysial and neurohypophysial systems in species higher than amphibians. Methods: The appearance and Topographical distribution of endocrine and neuroendocrine cells and fibers in these systems were immunohistochemically examined in the larvae of Xenopus laevis: from immediately before hatching (stage 32, Nieuwkoop and Faber's classification) to the end of metamorphosis (stage 66). Results:(1) Each endocrine cell differentiated until the middle premetamorphic period. MSH cells intially appeared in the posterior half of the pituitary anlage at stage 35/36, followed by the fidderentiation of GH cells at stage 39 in the middle part, PRL cells at stage 46 in the anterior half of the pituitary anlage, and LH cells at stage 50 in the posterior two thirds of the pares distalis. With the progression of development, the cells which differentiated at early stages shifted from their intial positions; MSH cells, to the pars intermedia; and GH cells, to the posterior half of the pars distails. 2) oxytocin and vasopression fibers were observed at stage 47/48 in the median eminence, and converged to the pars nervosa at later stages. 3) Neruoenmorphic to prometamorphic peripd: SOM fibes, at stage 45: CRH, 47/48; GRH, 48; dopamine, 58; and LHRH, 60. The cells containing these hormones were observed in the (presumptive) preoptic and/or infundibular nucleei. Conclusion: These results suggest the floowing three chronological steps in the development of hypothalamo-hypophysial systems and their target organs: independent development of target organs at early developmental stages; appearance of hypophysial hormones to control the development of target organs at middle developmental stages; appearances of hypothalamoic hormones to control the function of maturation of the hypophysis at late developmental stages. © 1995 Wiley-Liss, Inc.     

180例垂体腺瘤的临床病理观察

目的：研究垂体腺瘤的临床激素过多症状与腺瘤组织激素检测之间的关系以及该病的发生、生物学行为分类。方法：对180例垂体腺瘤进行了临床病理分析。并对其中110例应用免疫组化ABC法检测了肿瘤的GH、PRL、ACTH、TSH、FSH、LH。结果：临床激素过多症状与激素检测相一致者占40%,且女性较男性相致者多,差异有显著性。免疫组化分型以PRL和GH腺瘤多见,多激素腺瘤以GH PRL腺瘤多见。结论：垂体腺瘤的免疫组化检测与形态功能相结合的分类方法简便易行较为实用。