Menstrual cycle and sensitivity of human fallopian tube to prostaglandins

1986 ◽  
Vol 251 (6) ◽  
pp. R1126-R1136
Author(s):  
M. Nozaki ◽  
Y. Ito
Keyword(s):  
Fallopian Tube ◽  
Physiological Role ◽  
Circular Muscle ◽  
Slow Waves ◽  
Menstrual Cycles ◽  
Human Fallopian Tube ◽  
Low Concentrations ◽  
Endogenous Prostaglandins ◽  
Spontaneous Contractions ◽  
Human Oviduct

The shapes and frequencies of spontaneous contractions of circular muscle strips of the human oviduct differ during the menstrual cycles. However, under given conditions, the frequency and amplitude of the contractions were continuously reduced during perfusion with Krebs solution. In the presence of prostaglandin (PG) synthesis inhibitors or an antagonist, a gradual and continuous reduction was no longer observed, and low concentrations (10(-15)-10(-10) M) of PGE2 markedly suppressed the amplitude and frequency of the spontaneous contractions. The highest sensitivity of smooth muscle cells to PGE2 was observed during the periovulatory phases. Spontaneous prepotentials followed by slow waves were observed, and the latter potentials triggered contraction of the tissue. PGE2 (10(-14)-10(-12) M) inhibited, and PGF2 alpha (10(-9)-10(-7) M) enhanced the frequency of these slow waves. The amount of PGE series released from the tissues was twice of PGF series. These results suggest that endogenous prostaglandins play a physiological role in the transport of ovum in the human fallopian tube as a result of the regulation of spontaneous membrane and mechanical activities.

Quantitative study of α-adrenergic receptors in circular and longitudinal muscle of isthmus of rabbit fallopian tube and in rabbit aorta

1977 ◽  
Vol 55 (5) ◽  
pp. 1102-1106
Author(s):  
K. Rajkumar ◽  
P. L. Sharma
Keyword(s):  
Fallopian Tube ◽  
Quantitative Study ◽  
Adrenergic Receptors ◽  
Adrenergic Receptor ◽  
Longitudinal Muscle ◽  
Circular Muscle ◽  
Rabbit Aorta ◽  
Practical Application ◽  
Human Fallopian Tube ◽  
Receptor Agonists And Antagonists

The affinity of phenylephrine (pD2 value) and KB value for phentolamine for the α-adrenergic receptors of circular and longitudinal muscle of isthmus of rabbit fallopian tube and rabbit aorta have been estimated. The affinity of both phenylephrine and phentolamine was significantly more for the α adrenoceptors of the longitudinal muscle of isthmus of rabbit fallopian tube and rabbit aorta than circular muscle of isthmus of fallopian tube.The results of this investigation suggest that α adrenoceptors of circular muscle of isthmus are atypical. If this holds good for the human fallopian tube, the development of selective α-adrenergic-receptor agonists and antagonists may be of potential practical application for the control of fertility.

Expression and function of KCNH2 (HERG) in the human jejunum

2003 ◽  
Vol 284 (6) ◽  
pp. G883-G895 ◽  
Author(s):  
A. M. Farrelly ◽  
S. Ro ◽  
B. P. Callaghan ◽  
M. A. Khoyi ◽  
N. Fleming ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Interstitial Cells Of Cajal ◽  
Circular Muscle ◽  
Slow Waves ◽  
Enteric Neurons ◽  
Longitudinal Smooth Muscle ◽  
Low Concentrations ◽  
Pair Sequence ◽  
And Function ◽  
Cells Of Cajal

Previous studies suggest that ether-a-go-go related gene (ERG) KCNH2 potassium channels contribute to the control of motility patterns in the gastrointestinal tract of animal models. The present study examines whether these results can be translated into a role in human gastrointestinal muscles. Messages for two different variants of the KCNH2 gene were detected: KCNH2 V1 human ERG (HERG) (28) and KCNH2 V2 (HERGUSO) (13). The amount of V2 message was greater than V1 in both human jejunum and brain. The base-pair sequence that gives rise to domains S3– S5 of the channel was identical to that previously published for human KCNH2 V1 and V2. KCNH2 protein was detected immunohistochemically in circular and longitudinal smooth muscle and enteric neurons but not in interstitial cells of Cajal. In the presence of TTX (10−6 M), atropine (10−6M). and l-nitroarginine (10−4 M) human jejunal circular muscle strips contracted phasically (9 cycles/min) and generated slow waves with superimposed spikes. Low concentrations of the KCNH2 blockers E-4031 (10−8 M) and MK-499 (3 × 10−8 M) increased phasic contractile amplitude and the number of spikes per slow wave. The highest concentration of E-4031 (10−6 M) produced a 10–20 mV depolarization, eliminated slow waves, and replaced phasic contractions with a small tonic contracture. E-4031 (10−6 M) did not affect [14C]ACh release from enteric neurons. We conclude that KCNH2 channels play a fundamental role in the control of motility patterns in human jejunum through their ability to modulate the electrical behavior of smooth muscle cells.

Electrical and mechanical effects of acetylcholine and substance P in subregions of canine colon

1992 ◽  
Vol 262 (2) ◽  
pp. G298-G307 ◽  
Author(s):  
K. D. Keef ◽  
S. M. Ward ◽  
R. J. Stevens ◽  
B. W. Frey ◽  
K. M. Sanders
Keyword(s):  
Substance P ◽  
Circular Muscle ◽  
Muscle Layer ◽  
Proximal Colon ◽  
Slow Waves ◽  
Circular Muscle Layer ◽  
Long Duration ◽  
Low Concentrations ◽  
Excitatory Neurotransmitters ◽  
Circular Layer

Effects of acetylcholine (ACh) and substance P on the electrical and mechanical activities of the circular muscle layer of the canine proximal colon were studied. Because this muscle layer is bordered by two different pacemaker regions, responses from segments containing either a single pacemaker region or no pacemaker region were compared with responses of the complete muscle layer. Concentration-response relationships for ACh and substance P were similar between the various segments, suggesting that receptors for these agonists are expressed throughout the layer. The dominant contractile pattern induced by ACh and substance P in each segment was a 1- to 3-cycle/min rhythm. In a like manner, these agonists also elicited an electrical pattern in which a long-duration slow wave occurred one to three times per minute between short-duration slow waves. Low concentrations of nifedipine (0.01 microM) selectively antagonized the 1- to 3-cycle/min rhythm. In circular muscles with no pacemaker region, ACh (1 microM) caused depolarization, induced oscillations in membrane potential averaging 24 +/- 5 mV in amplitude and 2.9 +/- 0.9 cycles/min in frequency, and generated rhythmic contractions at the same frequency. This "interior" circular muscle was functionally innervated by cholinergic excitatory nerves. Exposure to ACh (1 microM) did not alter the conduction of slow waves through the thickness of the circular layer. In summary, the excitatory neurotransmitters, ACh and substance P, induce a dominant electrical and contractile rhythm throughout the circular muscle layer that is different from the spontaneous rhythms produced at either the myenteric or submucosal border.

ENDOCRINE ACTIVITY OF THE HUMAN FALLOPIAN TUBE

1969 ◽  
Vol 61 (1_Suppl) ◽  
pp. S80 ◽  
Author(s):  
Hubertus A. van Leusden
Keyword(s):  
Fallopian Tube ◽  
Endocrine Activity ◽  
Human Fallopian Tube
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