scholarly journals Adrenergic re-innervation of smooth muscle of nictitating membrane by preganglionic sympathetic fibres

1972 ◽  
Vol 220 (1) ◽  
pp. 211-227 ◽  
Author(s):  
B. Ceccarelli ◽  
F. Clementi ◽  
P. Mantegazza
Keyword(s):  
Smooth Muscle ◽  
Nictitating Membrane

Regulation of postsynaptic alpha-1 adrenoceptors in smooth muscle of the cat nictitating membrane

1990 ◽  
Vol 21 (6) ◽  
pp. 514-518
Author(s):  
�. N. Telina ◽  
S. V. Kirshin ◽  
R. S. Nizamov ◽  
R. Kh. Akhmedzyanov ◽  
Kh. S. Khamitov
Keyword(s):  
Smooth Muscle ◽  
Nictitating Membrane ◽  
Cat Nictitating Membrane

Responses of smooth muscles to quick stretch; relation of stretch to conduction

1960 ◽  
Vol 198 (5) ◽  
pp. 921-925 ◽  
Author(s):  
Geoffrey Burnstock ◽  
C. L. Prosser
Keyword(s):  
Smooth Muscle ◽  
Membrane Potential ◽  
Critical Level ◽  
Smooth Muscles ◽  
Taenia Coli ◽  
Nictitating Membrane ◽  
Active Muscle ◽  
Gap Measurement ◽  
Sucrose Gap ◽  
Visceral Muscles

Quick stretches applied to isolated strips of visceral muscles elicit contractions and electrical responses, similar stretches elicit no responses from blood vessels and nictitating membrane. Highly excitable muscles gave repetitive responses. Spontaneously active taenia coli relaxed in response to stretch and electrical activity diminished correspondingly. The membrane potential (sucrose gap measurement) decreased during stretch; spikes appeared at a critical level of depolarization. A single initial spike sometimes occurred before membrane depolarization. The membrane potential of spontaneously active muscle increased during stretch. Strips of smooth muscle mechanically immobilized in the center showed conduction from one side to the other; signals for both activation and relaxation were conducted. It is concluded that conduction can occur in absence of stretch, that quick stretch can alter membrane potential and thus alter excitability of smooth muscle.

In Vitro Responses of Nictitating Membrane to Drugs and to Denervation

1956 ◽  
Vol 186 (1) ◽  
pp. 152-156 ◽  
Author(s):  
William C. Wescott ◽  
Herbert E. Christensen ◽  
Amedeo S. Marrazzi
Keyword(s):  
Smooth Muscle ◽  
Electrical Impedance ◽  
In Vivo Studies ◽  
Isometric Contractions ◽  
Nictitating Membrane ◽  
Smooth Musculature ◽  
Permeability Studies ◽  
Isotonic Contractions

The smooth musculature of the cat's nictitating membrane, whose characteristics make it interesting and suitable for permeability studies as measured by transverse electrical impedance, has been studied in vitro. The inferior smooth muscle was removed, divested of its connective tissue covering, and mounted in a controlled temperature muscle bath composed of oxygenated ringer buffered with phosphate and containing glucose. Isotonic contractions were recorded on a kymograph using a frontal writing lever. The responsiveness of the muscle to adrenergic and cholinergic drugs was qualitatively in agreement with the results reported in in vivo studies. The cholinesterase inhibitor DFP enhances responsiveness to ACh without otherwise affecting brane length. ACh responsiveness is counteracted by small amounts of atropine. Denervated membranes exhibited a lowered threshold for adrenaline and noradrenaline—the sensitization being greater for the latter—and a lack of response to ephedrine. A method for recording isometric contractions by a mechano-electronic transducer has been developed for use in the conductance studies that are to follow. It is believed that, in addition to its use in study of permeability, this preparation will be of value in further elucidating the mechanism of action of various agents acting at autonomic neuro-effector junctions.

Effects of intracranial stimulation on denervated nictitating membrane of the cat

1961 ◽  
Vol 200 (5) ◽  
pp. 901-908 ◽  
Author(s):  
Alan B. Rothballer ◽  
Seth K. Sharpless
Keyword(s):  
Smooth Muscle ◽  
Cranial Nerves ◽  
Intracranial Stimulation ◽  
Optimal Conditions ◽  
Nictitating Membrane ◽  
Direct Stimulation ◽  
Greater Superficial Petrosal Nerve ◽  
Chronic Denervation ◽  
The Brain ◽  
Stimulation Of

The effect of intracranial stimulation on the chronically denervated nictitating membrane of the encéphale isolé cat has been studied. After eliminating sympathoadrenal discharge, we found that the nictitating membrane responds to direct stimulation of the brain stem and certain cranial nerves through: 1) an intrinsic sensitivity to direct mechanical stimulation which develops in the smooth-muscle fibers of the nictitating membrane after chronic denervation; 2) an effect by way of the greater superficial petrosal nerve, producing retraction of the nictitating membrane from diffusion of acetylcholine onto the sensitized smooth muscle from secretomotor fibers innervating nearby orbital glands; and 3) finally, after exclusion of cranial nerve effects, one can still, under optimal conditions, obtain retraction of the nictitating membrane after stimulation of the reticular formation, an effect that is tentatively ascribed to the release of a humoral factor from some intracranial source. The bearing of these findings on previous work in which the nictitating membrane has been used as an indicator of circulating neurohumors is discussed.

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