Responses of the Rabbit and Cat Urinary Bladders in Situ to Drugs and to Nerve Stimulation

Abstract

The response to atropine, hexamethonium, nicotine, emepronium bromide and some adrenergic compounds has been studied on the urinary bladder of the rabbit and the cat. It was shown that atropine caused a very small or no reduction in the response to electrically stimulated parasympathetic nerves in the urinary bladder of the rabbit. In the cat a dose dependent blockade was obtained after atropine administration. The stimulating response was abolished by hexamethonium or nicotine, suggesting that there are nicotinic receptors in the parasympathetic pathway. It is possible that the parasympathetic nerves running to the rabbit urinary bladder end in such nicotinic receptors on the effector cells in the detrusor muscle. Emepronium bromide, a potent anticholinergic compound, used clinically as a urological drug, was found to block the stimulatory response, which was interpreted as an effect on parasympathetic nicotinic receptors. Experiments with isoprenaline, adrenaline and noradrenaline showed that there are adrenergic α‐ and β‐receptors in the urinary bladder of the rabbit.

The effects of nicotine on spontaneous contractions of cat urinary bladder in situ

“…Different sub-types of adrenoceptors on the wall of the urinary bladder exist but excitatory a-adrenoceptors (Edvardsen, 1968a;Tiara, 1972;Elmer, 1974;Creed, 1979) (Edvardsen 1968b;Edvardsen & Setekleiv 1968;de Groat, 1975, Hindmarsh etal., 1977Creed 1979). The sudden increase followed by a decrease in intravesicular pressure produced by nicotine and DMPP in dogs, cats, rabbits and ra;s have been ascribed to an indirect action via autonomic ganglia from which the postganglionic motor nerves to the bladder arise (Chen et al, 1954;Gyermek 1961;1962;Garret 1963;Vanov 1965;Goldenberg 1965;Sjostrand et al, 1972). In the cat urinary bladder in situ, stimulation of the hypogastric nerve caused a contraction followed by cessation of rhythmic contractions and by a reduction of bladder tone (relaxation) (Edvardsen 1968b;Edvardsen & Setekleiv 1968).…”

“…Nicotine and dimethyl-phenylpiperazinium (DMPP) have been shown to contract and then relax the cat urinary bladder in situ (Edmunds & Roth, 1920;Goldenberg, 1965). In dogs and cats an indirect excitation of autonomic ganglia may be responsible for the vesicular motility induced by nicotine and DMPP (Chen et al, 1954;Gyermek, 1961;Larson et al, 1961;Garret, 1963;Goldenberg, 1965;Sjostrand et al, 1972), parasympathetic ganglia in the pelvic plexus that discharge motor impulses to the bladder; sympathetic ganglia are probably not involved (Vanov, 1965). However, Goldenberg (1965) concluded that the contractions of the urinary bladder to nicotine are due to stimulation of parasympathetic nerves but the transmitter liberated from these nerves must be a substance other than acetylcholine, histamine or 5-hydroxytryptamine.…”

Pharmacological studies of the uninhibited neurogenic bladder

“…The present results contrast with those reported by Sjiistrand et al (1972), who observed in cats a rise in the intravesical pressure after the injection of high doses of emepronium (0.5-4 mg/ kg) and atropine (0.5-12 mg/kg). The findings of Sjostrand et al (1972) may be explained by the increase in bladder irritation following high doses of atropine; namely the third possibility discussed above.…”

Wall mechanics of the rat bladder. II. Hydrodynamic studies in the frequency domain

“…When using the technique described in this report, the phase shift of the measurement system (low pass filter) will 'balance' that of the bladder wall (high pass filter) at a frequency of approximately 0.5 Hz where the pressure-volume loop showed to be almost linear for small volume changes. The effects of parasympathetic nerve stimulation and agents on bladder tonus are well known as well as the inhibitory effects ofanticholinergics (Hendersson & Roepke 1934, Hambourger et al 1950, Vanov 1965, Edvardsen 1967, Holmquist 1968, Sjostrand et al 1972. The reason for using these drugs was merely to show the simple assessment of pharmacological in vivo effects on bladder wall elasticity by using this technique.…”