Research highlights from the literature

The peptide catestatin is produced from the precursor protein chromogranin A. Apparently, catestatin regulates autonomic nervous system function through blockade of ganglionic nicotinic acetylcholine receptors. A recent study suggests that genetic polymorphisms affecting catestatin may have a bearing on human blood pressure regulation. In a study in autonomic failure patients, inhibition of carbohydrate reabsorption with the alpha glucosidase inhibitor acarbose attenuated postprandial hypotension. The study may be therapeutically relevant. The neuronal norepinephrine transporter affects cardiovascular regulation through combination of central nervous and peripheral mechanisms. In a new study, pharmacological norepinephrine transporter inhibition elicited a profound pressor response in patients with central autonomic failure due to multiple system atrophy. Blood pressure did not respond in patients with peripheral autonomic neuropathies. The investigators suggest that the pressor response results from peripheral norepinephrine transporter inhibition that is unopposed by a central sympatholytic effect. In vitro, human growth hormone has a neuroprotective effect. A small placebo-controlled clinical trial evaluated the safety of human recombinant growth hormone treatment in patients with multiple system atrophy. The intervention was well tolerated. Unfortunately, the study was to small to evaluate efficacy.