Pharmacology and Nerve Endings

The capillary dilator substances in dry powders of spinal roots; a possible role of adenosine triphosphate in chemical transmission from nerve endings

“…It seems possible that such stimulation releases ATP or a similar substance from the nerve endings, and that the substance acts on the blood vessels to produce antidromic vasodilatation. It is not certain whether the neurones responsible for antidromic vasodilatation are sensory neurones or whether they belong to a special efferent system (Lewis, 1942), but it is reasonable to suppose that the chemical substance liberated at their peripheral endings might also be produced in the central nervous system by an afferent sensory impulse (Dale, 1935). It thus becomes of interest to consider the general hypothesis that ATP acts as a physiological transmitter of impulses at certain nerve endings in the central nervous system.…”

“…The vasodilatatioii which results from antidromic stimulation of sensory nerves has suggested to several authors (Dale, 1935;Hellauer & Umrath, 1948), that the transmission of impulses from both peripheral and central endings of sensory fibres may be mediated by a chemical substance possessing a vasodilator action. In searching for such a substance in nervous tissue, Hellauer & Umrath (1947 found that potent vasodilator activity was present in extracts of dorsal but not of ventral roots.…”

Brief Presentation of the Story and Present Status of Studies of the Vertebrate Cholinergic System

“…Feldberg 1987). Although Henry Dale (1935) and William Feldberg (1945) 1993-VOL. 9, NO.3 anism for the termination of action of a chemical trans mitter that would be sufficiently rapid to prevent clog ging; however, the rapidity of action of acetyl ChE (AChE) became known in the 1950s helping Eccles's conversion (Karczmar 1991).…”

THE EFFECTS OF SENSORY DENERVATION ON THE RESPONSES OF THE RABBIT EYE TO PROSTAGLANDIN E1, BRADYKININ AND SUBSTANCE P

“…Histamine-like substances (Ungar, 1935), histamine itself (Kwiatkowski, 1943;Ibrahim, Stella & Talaat, 1951), adenosine 5'-triphosphate (ATP, Holton, 1959), kinins (Chapman, Ramos, Goodell & Wolff, 1961) and prostaglandins (Perkins, 1975) have all been proposed as candidates, but are now generally discounted. Dale (1935) had suggested that in view of the bipolar structure of the sensory neurone the transmitter at the central end of primary afferents was unlikely to differ from that at the periphery. It now seems likely that substance P is the central transmitter (Lembeck, 1953;Amin, Crawford & Gaddum, 1954;Hokfelt, Kellerth, Nilsson & Pernow, 1975;Otsuka & Konishi, 1976) and so it is possible that it may also be a peripheral mediator, evidence for which has been found in the skin (Hokfelt et al, 1975) and in the teeth (Olgart, Gazelius, Brodin & Nilsson, 1977).…”