In Vitro Isometric Studies of Ureteral Smooth Muscle

THE presence of both alpha and beta adrenergic receptors has been demonstrated in the caudal third of the pig ureter by means of the technique of Trendelenburg (Deane, 1967) and in all segments of the canine ureter by means of the isometric strip technique (Malin et al., 1968). Activation of the " dominant " alpha receptors by adrenaline and noradrenaline produces a contraction of the smooth muscle. The presence of the " recessive " beta receptors can be revealed by activating the beta receptors directly, or by blocking the alpha receptors and then activating the " unblocked " beta receptors with adrenaline or noradrenaline.It has been suggested that activation of these beta adrenergic receptors during bladder contraction may give rise to vesico-ureteric reflux. This may also account for aperistaltic distal segmental dilatation of the ureter occasionally observed in patients with uretero-vesical obstruction.The aim of this present study was to examine the human ureter to determine if both alpha and beta adrenergic receptors were present.Materials and Method.-Two methods of investigation were employed. The apparatus used by R. F. D. is as described for the Trendelenburg preparation (Trendelenburg, 1917). Specimens of lower third of human ureter were obtained fresh at operation, placed in Krebs solution and transported to the laboratory. Three preparations were obtained. Two were from males and 1 from a female. In each case the bladder was the seat of fairly advanced cancer and subsequent histology of the ureter showed cancerous infiltration.J. M. M. and S . B. used the isometric strip method of investigation (Malin et al., 1968).Specimens from all levels of human ureter were obtained at operation, placed in Locke's solution and transported to the laboratory. Twenty-two normal preparations were obtained from renal transplant donors and 57 experiments were performed.Results.-Trendelenburg's Technique.-The lengths of lower third of the human ureter responded with spontaneous contractions with Trendelenburg's technique. It is presumed that the amplitude of contraction would have been greater if the tissue had not been the seat of neoplastic infiltration. Prolonged experimentation was not possible also because of the cancerous process, the preparation becoming easily fatigued.Only the changes in length are recorded for convenience but the volume change closely followed the changes in length (Fig. 1).Adrenaline hydrochloride at a concentration of 10-5 g./ml. of the salt and L-noradrenaline bitartrate at a concentration of 10-6 g./ml. of the salt both increase the tone and frequency of contraction.Isoprenaline (isoproterenol or D, L-N-Isopropylnoradrenaline), at a concentration of 10-5 g./ml. of the base decreased the amplitude and frequency of contraction.

show abstract

“…

…”

mentioning

confidence: 99%

Characterisation of Adrenergic Receptors in Human Ureter1

Malin

Deane

Boyarsky

1970

British Journal of Urology

Self Cite

157

View full text Add to dashboard Cite

show abstract

“…Many interesting reports that the peristaltic move ments of the ureters are introduced by an activation of the pacemaker system (5,10,15) and that the isolated ureter has a spontaneous activity (10,11) or not (21) let us fur ther analyze the uropharmacological characteristics of the ureteral smooth muscle itself. In the present study, iso lated dog ureters were divided into three portions (upper, middle and lower portion), which are reported to receive different autonomic innervation (6,14).…”

Section: Discussionmentioning

confidence: 99%

Actions of Some Autonomic Drugs on Isolated Dog Quiescent Ureter

Ueda¹,

Yano²,

Sakanashi³

et al. 1981

Eur Urol

View full text Add to dashboard Cite

“…Atropine has no effect on spontaneous contractions at doses which abolish contractions induced by acetylcholine. Most animals species investigated, including cat (Lucas, 1908), dog (Roth, 1917;Malin et al, 1968), pig (Longrigg, 1974a & b;Muschat, 1929), rabbit (Gosling & Waas, 1971), rat (Finberg & Peart, 1970) and water-buffalo (Gould et al, 1955), have been shown to possess excitatory a-adrenoceptors as in human tissue. Less consistent responses have been found when using f3-adrenoceptorand muscarinic-agonists.…”

Section: Effect Of Drugsmentioning

confidence: 99%

“…Although the adrenoceptors do receive a functional innervation, there is no such innervation of the muscarinic receptors (Longrigg, 1974b). Other species such as dog 0306-5251 82/040461-08 $01.00 and water-buffalo have been shown to respond to muscarinic agonists although 'to a lesser degree than seen with a-adrenoceptor stimulation' (Gould et al, 1955;Malin et al, 1968).…”

Section: Effect Of Drugsmentioning

confidence: 99%

The upper urinary tract.

Longrigg¹

1982

Brit J Clinical Pharma

View full text Add to dashboard Cite

In Vitro Isometric Studies of Ureteral Smooth Muscle

Cited by 31 publications

References 5 publications

Characterisation of Adrenergic Receptors in Human Ureter1

Characterisation of Adrenergic Receptors in Human Ureter1

Actions of Some Autonomic Drugs on Isolated Dog Quiescent Ureter

The upper urinary tract.

Contact Info

Product

Resources

About