Injection sclerotherapy in portal hypertension.

Mucus synthesis by the human gall bladder EDITOR,-I was interested to read the papers by Rhodes and colleagues concerning mucus synthesis by the human gall bladder, its apparent inhibition by aspirin, and other non-steroidal anti-inflammatory drugs (NSAIDs), and the suggestion that aspirin might prevent cholesterol gall stone formation by this action As gall bladder mucus glycoprotein (mucin) is a secre-tory product, however, estimates of mucin synthesis must take account of secreted mucin as well as tissue mucin concentrations. These papers have reported tissue concentrations only. This is curious, especially as it is the secreted component that is thought to play a part in cholesterol gall stone formation.' It cannot be assumed that secreted mucin necessarily reflects tissue concentrations (it ranges from 30-50% of total mucin synthesis in the prairie dog model). 2 Although aspirin and other NSAIDs reduced mucin concentrations in gall bladder explants in vitro their effects on mucin secretion in vitro were not presented. In the in vivo trial performed by the authors, however, mucin concentrations in the gall bladder bile of patients treated with aspirin were no lower than those in controls. These papers have not shown an effect of aspirin or other NSAIDs on gall bladder mucin synthesis or secretion. The case remains unproved. 1 Lee SP, LaMont JT, Carey MC. Role ofgallbladder mucus hypersecretion in the evolution of cholesterol gallstones. Studies in the prairie dog. Inhibition of prostaglandin synthesis fails to prevent gallbladder mucin hypersecretion in the cholesterol-fed prairie dog. Reply EDITOR,-We thank Mr O'Leary for his interest in our papers but find his comments a little difficult to follow. He is quite correct when he states that we did not measure secreted mucin in the supernatant of our culture plates and this would provide additional information about the actions of aspirin in vitro. His conclusion that these papers 'have not shown any effect of aspirin on gall bladder mucin synthesis' is, however, incorrect. Both in vitro and in vivo we were able to show consistent inhibition of mucin synthesis. Aspirin and NSAIDs undoubtedly have significant actions on the human gall bladder. This is confirmed by epidemiological findings,' biochemical studies such as these and other work in humans,2 and motility work.3 Whether these actions are clinically or therapeutically significant does indeed remain open to question but no doubt will be answered through the pages of this and other journals over the next five years.