cyberprimate said:
I've just read on a French site that many vasodilators were tried on the scalp with no additional hair growth. Hence their conclusion that Minoxidil's beneficial action on air wouldn't be vasodilation, but its similarity with nitric acid that boosts keratine synthesis, and opens potassium channels at the follicle cells.
Exactly! I've pointed out several times over the years that many other vasodilators don't have the same hairgrowth effect as ones in the same chemical family as minoxidil and diazoxide; that effect appears to be a direct function of their similarity to nitric oxide. Dr. Proctor has said
repeatedly on alt.baldspot that nitric oxide is a chemical "signal" to hair follicles to grow!