FSH-induced Sertoli cell proliferation in the developing rat is modified by beta-endorphin produced in the testis

To probe the possible role of endogenous opiates in Sertoli cell proliferation during testicular development, the effect of interfering with beta-endorphin action either in vivo or in vitro was determined. The percent of Sertoli cells dividing was measured with quantitative autoradiography in [methyl 3H]-thymidine-exposed fetal testes maintained in organ culture with or without FSH, in the presence or absence of the opiate blocker naloxone. After 1 or 2 days in culture, naloxone enhanced the rise in Sertoli cell proliferation seen with FSH alone, while 2 days of incubation with naloxone alone markedly raised the percent of Sertoli cells dividing above that in untreated cultures. Moreover, when endorphin antiserum was injected directly into testes of pups and Sertoli cell proliferation in vivo measured 8 or 19 h later, there was a dramatic increase in the percent of Sertoli nuclei labeled by [methyl 3H]-thymidine compared to controls. These findings suggest that beta-endorphin produced within the testis is a paracrine modifier of the proliferative response of Sertoli cells to FSH. This implies that communication occurs between Leydig and Sertoli cells during development via endogenous testicular opiates.     

A novel rat model of chronic fibrosing cholangitis induced by local administration of a hapten reagent into the dilated bile duct is associated with increased TNF-alpha production and autoantibodies

BACKGROUND/AIM: The cholangiopathies represent hepatobiliary diseases in which bile-duct epithelial cells are targets for destructive processes, including immune-mediated damage. We describe a novel rat model of chronic fibrosing cholangitis induced by administration of the hapten reagent 2,4,6-trinitrobenzenesulfonic acid (TNBS) into the dilated bile duct. METHODS: The common bile duct was dilated due to a mild stenosis in 8-week-old female Lewis rats. TNBS (50 mg/kg) was injected during a second laparotomy. RESULTS: TNBS-treatment reproducibly resulted in chronic fibrosing cholangitis. In retrograde cholangiography the bile ducts showed irregularities, beading and strictures. Alkaline phosphatase levels remained abnormal throughout the study period. Immunohistochemical staining showed an increased number of macrophages, CD3+ T-lympbocytes and MHC class II antigen upregulation. The spontaneous interferon-gamma, tumor necrosis factor-alpha and interleukin-10 production of liver-derived mononuclear cells was increased. Anti-neutrophil cytoplasmic antibodies with specificity against myeloperoxidase, catalase and actin were found between 1 and 12 weeks after TNBS injection. CONCLUSIONS: We established a novel rat model of chronic fibrosing cholangitis with histologic, cholangiographic, serologic and immunologic similarities to human primary sclerosing cholangitis. This model may be used to study pathomechanisms of chronic cholangitis without concomitant inflammatory bowel disease.     

Adrenocorticotropin-independent bilateral macronodular adrenal hyperplasia: an unusual cause of Cushing's syndrome

Inappropriate ACTH secretion with bilateral diffuse or macronodular adrenal hyperplasia is the most common cause of Cushing's syndrome. This report describes a patient with Cushing's syndrome and feminization due to ACTH-independent bilateral macronodular adrenal hyperplasia. A 47-yr-old black man presented with Cushingoid features, diabetes mellitus, hypertension, impotence, and gynecomastia. Urinary cortisol and 17-hydroxycorticosteroid excretion were 94 nmol/mmol creatinine (normal, less than 32) and 5.8 mumol/mmol creatinine (normal, 0.6-3.6), respectively. Both decreased by less than 30% after administration of dexamethasone (8 and 16 mg/day), and urinary 17-hydroxycorticosteroid excretion did not increase after metyrapone (750 mg, orally, every 4 h for six doses). Plasma ACTH was undetectable (less than 1 pmol/L) and was not stimulated by administration of metyrapone or ovine CRH. Serum testosterone was 5.2 nmol/L (normal, 7-30), FSH was 5 U/L (normal, 3-18), LH was 2.8 U/L (normal, 1.5-9.2), and estrone was 767 pmol/L (normal, 55-240). Both adrenal glands were enlarged, with a total weight of 86 g (normal, 8-10), and contained multiple nodules (diameter, greater than 0.5 cm) composed of two active cell types, one of which was also observed between the nodules. Cushing's syndrome with feminization due to ACTH-independent bilateral macronodular adrenal hyperplasia is an unusual process of unknown etiology that should be included with the other known causes of Cushing's syndrome.     

Rehabilitation of therapy-related cognitive deficits in patients after hematopoietic stem cell transplantation

Neuropsychological deficits are potential side effects of hematopoietic stem cell therapy (HSCT). Systematic data on the long-term course of and therapeutic options for these consequences are limited. One hundred fifty-seven patients were screened for cognitive deficits following HSCT for malignant diseases at an in-patient oncologic rehabilitation clinic. Patients showing evidence of impairment were randomly assigned to one of two training groups: individualized PC-supported training or neuropsychological group therapy. The control group consisted of patients who received no specific training. During in-patient rehabilitation, the results of a comprehensive neuropsychological test battery improved significantly in all three groups, and no specific intervention effects were identified. Neuropsychological deficits were still evident in a subgroup of patients 6 months later. Correlation between neuropsychological testing and patients' self-evaluation of cognitive functioning in daily life was generally low. Sustained attention and verbal-semantic memory played the main role for self-appraisal and in the designation as 'neuropsychologically impaired'. In conclusion, a substantial number of patients revealed evidence of cognitive deficits a long time after HSCT. There is a need for more studies and for the development of differentiated rehabilitative measures for such therapeutic consequences.     

Splenectomy as an adjuvant measure in the treatment of severe aplastic anaemia

The role of splenectomy in aplastic anaemia (AA) is controversial. The hazards of operating on a severely pancytopenic patient, the fear of compromising the patient’s immune function, and the improvement of non-surgical treatment have made splenectomy unpopular in this disease. We have evaluated positive and adverse effects of splenectomy in 80 patients with severe aplastic anaemia (SAA) treated with antilymphocyte globulin (ALG) (group A), using 52 nonsplenectomized ALG patients as controls (group B). All patients survived the operation. Nonfatal complications of surgery occurred in 10 (12.5%). Splenectomy induced a significant increase of peripheral blood neutrophils, reticulocytes and platelets within 2 weeks, followed by a continuous increase of all values over the following weeks. 28/132 patients (21%) developed a late clonal disorder of haemopoiesis, paroxysmal nocturnal haemoglobinuria (PNH) or myelodysplastic syndrome (MDS), or both. Their incidence was identical in groups A and B. 13/28 (59%) died, 10/17 (59%) in group A and 3/11 (27%) in group B (not significant (n.s.)). Overall probability of survival at 18 years after ALG was 51 ± 6% for group A and 61 ± 7% for group B (n.s.). We conclude that splenectomy in AA is safe. It induces an immediate increase of peripheral blood counts and, thereafter, a continuous improvement of haemopoiesis. It does not increase the incidence of late clonal complications but has a borderline effect on mortality from these disorders. Splenectomy should be reconsidered in selective nontransplanted patients who have prolonged transfusion requirements despite otherwise optimal treatment.     

Detailed kinetic analysis of adrenocorticotropin secretion by dispersed rat anterior pituitary cells in a microperifusion system: effects of ovine corticotropin-releasing factor and arginine vasopressin

We have developed a microperifusion system in which we have examined the ACTH secretory responses of acutely dispersed normal rat anterior pituitary cells to ovine CRF (oCRF) and arginine vasopressin (AVP), alone and in combination. The system approached square-wave stimulus hydrodynamics. ACTH secretion was observed within 5 sec of exposure to either secretagogue and reached a maximum within 20-40 sec. ACTH secretion remained constant for as long as oCRF was perifused and then fell gradually toward the basal level. Persistent ACTH release after oCRF perifusion was stopped could not be explained by persistence of oCRF in the perifusion chamber. In contrast to the response to oCRF, ACTH secretion fell progressively toward basal despite continued AVP perifusion. AVP had a synergistic effect with oCRF only if it was perifused simultaneously with oCRF or within 30 sec after oCRF was stopped; it had no synergistic effect if perifused immediately before oCRF. Simultaneous perifusion of oCRF and AVP resulted in an oCRF-like response of greater magnitude, whereas sequential perifusion of oCRF followed by AVP resulted in the usual plateau response to oCRF followed by the initial spike response characteristic of very high concentrations of AVP alone and a subsequent rapid decrease in secretion despite continued perifusion of AVP. The different kinetic response profiles suggest that oCRF and AVP act via different intracellular signal transduction pathways, and the time and sequence dependency of their synergism suggests that the factors that mediate their interactions have different intracellular half-lives. The microperifusion system appears to be uniquely suited to detailed kinetic analysis of anterior pituitary hormone secretion and the intracellular pathways through which secretagogues act and interact.