HISTOCHEMICAL STUDIES OF THE RELATIONSHIP OF CHROMAFFIN CELLS AND ADRENERGIC NERVE FIBERS TO THE CARDIAC GANGLIA OF SEVERAL SPECIES

摘要: Atrial cardiac ganglia of rats, cats, guinea pigs and mice were studied for catecholamine-containing structures by a histochemical fluorescence method. Very fine varicose adrenergic fibers seen in close apposition to some the cholinergic ganglion cells. The administration monoamine oxidase inhibitor followed 3,4-dihydroxyphenylalanine. resulted appearance catecholamine (CA) This suggests that at least parasympathetic cells are capable taking up 3,4-dihydroxyphenylalanine synthesizing metabolizing CA. Intense CA-fluorescent resembling adrenal medullary found confines atrial all species. Positive chromaffin silver-staining reactions observed these cat atria. considered be as such can regarded an extraneuronal CA pool. One dose reserpine (5 mg/kg) administered 24 or 4 hr before sacrifice does not appear affect content Larger doses longer period time lead reduction intensity Application both acetylcholinesterase stains same section revealed most cellsare innervated acetylcholinesterase-staining nerve fibers. Some receive postganglionic innervation from heart. It is suggested system contained around functions self-controlling inhibitory influence on ganglionic transmission.