62 cryptorchid boys aged 2–6 years were selected at random either for surgical or for hormonal LH-RH treatment. As all biopsies from boys operated show typical histological and ultrastructural signs of cryptorchidism, it can be concluded that only true cryptorchid patients are included in our study. LH-RH treatment was successful in 16 (55%) of 31 boys. Median 30-min response values to LH-RH test of LH were initially normal in all boys. Those treated successfully remain normal after treatment whereas unsuccessfully treated patients have significantly lower LH 30-min response values at the end of the 4 weeks of LH-RH treatment. FSH response was not statistically different before or after treatment. This might indicate that a normal LH response is necessary for testicular descent. In the 15 boys operated after 4 weeks of unsuccessful LH-RH treatment, testes biopsies show recruitment of the Leydig cell precursors and development of juvenile Leydig cells with an increase in their content of lipoid droplets and smooth endoplasmic reticulum. No adverse effect on the number of spermatogonia could be observed after 4 weeks of LH-RH treatment.
The aim was to investigate the action of serotonin (5HT) on function of the ileocolonic junction (ICJ) in vivo. In anaesthetised rats, models were developed to study the effects of intra-aortic (ia) serotonin on ileocolonic and colonic transit, and the effects on transit of a number of 5HT receptor antagonists. In the first series of experiments, a bolus of saline labelled with 99mTc DTPA was instilled 20 cm proximal to the ICJ and transit was assessed three hours later by the geometric centre of the spread of isotope. In the second series, similar techniques were used on the postcaecal colon and transit assessed two hours later. In the third series of experiments, the effects of ia 5HT on ileal net fluid flux was evaluated by standard perfusion experiments with 14C polyethylene glycol (PEG) 4000 as a non-absorbable marker in rat plasma-like electrolyte solution. Compared with ia saline, 5HT accelerated ICJ transit significantly (p<005). This acceleration was comparable with the effect of ia bethanechol. The effects of 5HT on ICJ transit were inhibited by the intraperitoneal (ip) infusion ofatropine, the 5HT receptor antagonists, methysergide, ketanserin, zacopride, and the 5HT4 agonist, SC53116. Methysergide, zacopride, and SC53116 given with ia 5HT slowed ICJ transit to rates below those of ia saline alone. When these same agents were given together with ia saline, the ICJ transit was not significantly altered. Serotonin, at the dose that accelerated ICJ transit, did not significantly alter colonic transit or ileal fluid transport. In conclusion, 5HT is a potent pharmacological stimulant oftransit across the rat ICJ in vivo; the action of 5HT is mediated partly through muscarinic neurones and several 5HT receptor subtypes.
The plasma histamine levels were reported to increase in early hours of the morning in asthmatic patients. It was supposed that this phenomenon would also be observed in normal volunteers. In this study using twelve normal healthy volunteers the plasma histamine levels were examined in a pharmacokinetic manner. It could be shown that plasma histamine levels flow biorhythmic changes with 3 maxima and 3 minima. The acrophases of the maxima are 12.77 +/- 0.61, 19.33 +/- 0.78 and 5.42 +/- 1.83 h. The most important rise in plasma histamine levels was found in the early hours of the morning representing about 55% of the total histamine available in plasma.
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