Central control of feeding behavior by neuropeptide Y.

Obesity is a serious health problem in the Western societies, therefore its treatment has become the subject of intense interest in the scientific community. A significant number of recent publications enlist different central and peripheral factors which play important roles in the regulation of food intake, body weight and energy expenditure. Neuropeptide Y, a 36 amino acid peptide, which is quite abundant in the brain, seems to be one of the more important players in these regulations. Recently five NPY receptors have been cloned and pharmacological evidence strongly supports the existence of a sixth receptor. There are many contradictory findings regarding which NPY receptor mediates the effect of NPY on food intake. This article will review the effects of NPY on the regulation of food intake and energy expenditure and will discuss the pharmacological and molecular evidence as to which NPY receptor(s) mediate this effect. The review will also summarize the progress which has been made in the design of novel NPY-ergic ligands, especially NPY receptor antagonists, for potential use in the treatment of obesity.

Pharmacology of BMY 20064, a potent Ca2+ entry blocker and selective alpha 1-adrenoceptor antagonist.

BMY 20064 is a dihydropyridine Ca2+ entry blocker with potent and selective alpha 1-adrenoceptor antagonist properties. The drug was equal in potency to nifedipine as a Ca2+ entry blocker in depolarized smooth muscle preparations. It was less active than nifedipine in antagonizing Ca2+-induced contractions of isolated guinea pig papillary muscles paced at 0.2, 1.0, or 2 Hz. BMY 20064 was a potent (0.1-0.2 X prazosin) and selective alpha 1-adrenoceptor antagonist in radioligand binding assays and in ganglion-blocked anesthetized rats challenged with phenylephrine. BMY 20064 blocked both the K+ and alpha 1-adrenergic agonist-induced increases in 45Ca uptake into rabbit aortic rings. The drug was more effective than nifedipine, prazosin, or combinations of the drugs in preventing ATP depletion of the rat heart during global ischemia. BMY 20064 was a potent antihypertensive agent in normotensive rats and in SHR. BMY 20064 administered intraarterially (i.a.) dilated both femoral and coronary arterial beds of the dog. Hemodynamic changes elicited by BMY 20064 in anesthetized dogs were similar to those induced by nifedipine. BMY 20064 appears to be a more effective myocardial antiischemic agent than nifedipine, prazosin, or combinations of nifedipine and prazosin. A drug of this type may be more efficacious than dihydropyridines in the management of ischemic episodes.