From depolarization-dependent contractions in gastrointestinal smooth muscle to aortic pulse-synchronized contractions

Figures & data

Figure 1 Voltage profiles of electrical activity in cat small intestinal smooth muscle.

Notes: Shown in the upper panel are three spontaneous slow waves with spikes superimposed on the peak of each slow wave. Recordings were made with intracellular microelectrodes. In the lower panel are three prolonged potentials recorded from a segment of cat small intestinal smooth muscle during incubation in calcium-free solutions containing ethylene glycol tetraacetic acid. Membrane potential depolarizes from approximately −70 mV to −40 mV after the change from normal solution to calcium-free solution. Note change in timescale between the upper and lower traces. Reproduced with permission from Mangel AW, Nelson DO, Rabovsky JL, Prosser CL, Connor JA. Depolarization-induced contractile activity of smooth muscle in calcium-free solution. Am J Physiol. 1982;242(1):C36–C40.⁸

Figure 2 Recording from cat small intestinal muscle segment of mechanical (upper) and electrical (lower) activity in normal solution (A), 7 minutes after change to calcium-free solution (B), and 50 minutes after change to calcium-free solution (C). As shown in (C), prolonged potentials triggered contractions. Electrical recordings were made with pressure electrodes. Calibration bar: A/B, 0.4 mV, 0.8 g, 16 seconds; C, 0.27 mV, 0.13 g, 10 seconds. Reproduced with permission from Mangel AW, Nelson DO, Rabovsky JL, Prosser CL, Connor JA. Depolarization-induced contractile activity of smooth muscle in calcium-free solution. Am J Physiol. 1982;242(1):C36–C40.⁸

Figure 3 Recording of electrical activity from a segment of rabbit aorta. In the upper trace, recordings are made in normal solutions containing calcium. In the lower trace, fast rhythmic potentials become apparent after a change to calcium-free solution. Recordings are made with a pressure electrode. Calibration bar: 1 mV, 4 seconds. Reproduced with permission from Mangel A, van Breemen C. Rhythmic electrical activity in rabbit aorta induced by EGTA. J Exp Biol. 1981;90:339–342.¹³

Figure 4 Simultaneous recording of tension (upper) and blood pressure (lower) from the rabbit aorta in vivo.

Notes: Vertical lines represent the onset of the pressure wave. Calibration bar: 0.6 g, 30 mmHg, 120 milliseconds. Basal blood pressure was 76 mmHg. The polarity of the upper trace was inverted from that originally recorded. Reproduced with permission from Mangel A, Fahim M, van Breemen C. Rhythmic contractile activity of the in vivo rabbit aorta. Nature. 1981;289(5799):692–694.²⁰

MangelAWNelsonDORabovskyJLProsserCLConnorJADepolarization-induced contractile activity of smooth muscle in calcium-free solutionAm J Physiol19822421C36C407058877

 PubMed Web of Science ®Google Scholar

MangelAvan BreemenCRhythmic electrical activity in rabbit aorta induced by EGTAJ Exp Biol1981903393426787163

 PubMed Web of Science ®Google Scholar

MangelAFahimMvan BreemenCRhythmic contractile activity of the in vivo rabbit aortaNature198128957996926947464936

 PubMed Web of Science ®Google Scholar