Cholinergic mediation of growth hormone secretion induced by thyrotropin-releasing hormone in cirrhotic patients.
In order to evaluate the possible involvement of muscarinic cholinergic receptors in the GH response to TRH in patients with liver cirrhosis, 8 males with post-hepatitic cirrhosis and 11 males with post-alcoholic cirrhosis were primed with the anticholinergic agent pirenzepine and tested with TRH. In addition, 10 male patients affected by piecemeal necrosis were tested in a similar manner. High basal concentrations of GH were found in all groups. None of the patients with piecemeal necrosis responded to TRH, whereas in patients with post-hepatitic and in post-alcoholic cirrhosis, TRH induced a significant rise in GH levels. The priming with pirenzepine (40 mg given iv 10 min before TRH) completely blocked the TRH-induced GH increase, but did not affect the TRH-induced TSH release. These data suggest that a muscarinic cholinergic pathway is involved in the anomalous response of GH to TRH in patients with liver cirrhosis. The lack of effect of pirenzepine on the TRH-stimulated TSH release suggests that the muscarinic cholinergic mediation is peculiar for the effect of TRH on GH secretion.
D000328:Adult; D013006:Growth Hormone / Q000097:blood / Q000378:metabolism*; D006801:Humans; D008099:Liver / Q000378:metabolism / Q000473:pathology; D008103:Liver Cirrhosis / Q000097:blood*; D008104:Liver Cirrhosis, Alcoholic / Q000097:blood*; D008297:Male; D008875:Middle Aged; D009336:Necrosis; D010890:Pirenzepine / Q000494:pharmacology; D011976:Receptors, Muscarinic / Q000378:metabolism*; D013973:Thyrotropin-Releasing Hormone
D011976:Receptors, Muscarinic; D010890:Pirenzepine; D013973:Thyrotropin-Releasing Hormone; D013006:Growth Hormone