Effects of prostaglandin F2α on the contractile responses of guinea-pig ileum to electrical stimulation

1983 ◽  
Vol 39 (7) ◽  
pp. 754-755 ◽  
Author(s):  
R. Radomirov ◽  
V. Petkov ◽  
S. Yanev
Keyword(s):  
Electrical Stimulation ◽  
Guinea Pig ◽  
Prostaglandin F2α ◽  
Guinea Pig Ileum ◽  
Contractile Responses

Effects of serotonin1-like receptor agonists on autonomic neurotransmission

1991 ◽  
Vol 69 (12) ◽  
pp. 1855-1860 ◽  
Author(s):  
K. H. Park ◽  
J. P. Long ◽  
J. G. Cannon
Keyword(s):  
Electrical Stimulation ◽  
Guinea Pig ◽  
Low Frequency ◽  
Facilitatory Effect ◽  
Nictitating Membrane ◽  
Guinea Pig Ileum ◽  
Contractile Responses ◽  
Receptor Agonists ◽  
Cat Nictitating Membrane ◽  
Pithed Rats

Serotonin1A receptor agonists, 8-hydroxy-2-(di-n-propylamino)tetralin and 10-methyl-11-hydroxyaporphine, inhibited electrical stimulation-induced contraction of the guinea-pig ileum. These agonists also inhibited the pressor and tachycardiac responses to low frequency (0.25 Hz) but not to high frequency (2.0 Hz) electrical stimulation of the sympathetic nervous system in pithed rats. Serotonin1B receptor agonist RU 24969 inhibited pressor and tachycardiac responses to both low and high frequencies of stimulation in pithed rats. In the cat nictitating membrane, serotonin1A receptor agonists did not alter contractions elicited by electrical stimulation (0.1–3.0 Hz). Serotonin not only contracted the cat nicitating membrane but also facilitated contractile responses to low frequency (0.1 – 1.0 Hz) stimulation. The contractile effect of serotonin in the cat nictitating membrane was blunted by bretylium, methysergide, and ketanserin, but not by metoclopramide. The facilitatory effect of serotonin was antagonized by methysergide, but not by ketanserin, pindolol, propranolol, or metoclopramide. These results suggest that serotonin1A receptors modulate autonomic neurotransmission in the guinea-pig ileum and pithed rats, but not in the cat nictitating membrane. Serotonin contracts the cat nictitating membrane via serotonin2 subtypes, while facilitating stimulated contractile responses through the serotonin1-like receptors.Key words: guinea-pig ileum, pithed rats, nictitating membrane, serotonin receptors.

Effects of neurotransmitter release on mucosal transport in guinea pig ileum

1983 ◽  
Vol 245 (6) ◽  
pp. G745-G750 ◽  
Author(s):  
H. J. Cooke ◽  
K. Shonnard ◽  
G. Highison ◽  
J. D. Wood
Keyword(s):  
Electrical Stimulation ◽  
Guinea Pig ◽  
Neurotransmitter Release ◽  
Short Circuit ◽  
Short Circuit Current ◽  
Scorpion Venom ◽  
Enteric Neurons ◽  
Sodium Absorption ◽  
Guinea Pig Ileum ◽  
Ileal Mucosa

Scorpion venom (Leiurus quinquestriatus), a substance that evokes neurotransmitter release by depolarizing neurons, was used to activate enteric neurons in short-circuited guinea pig ileum. Scorpion venom increased transmural potential difference and short-circuit current, and this response was similar to the increase that occurred after electrical stimulation of enteric neurons. The stimulus- or venom-evoked response in short-circuit current was abolished by tetrodotoxin. Atropine reduced by 47% the increments in short-circuit current produced by either electrical stimulation or venom. Scorpion venom increased active chloride secretion in short-circuited guinea pig ileal mucosa but had no significant effect on active sodium absorption, residual flux, or total tissue conductance. No morphological changes in transmission electron micrographs of ileal mucosa treated with scorpion venom were evident compared with controls. Alanine caused an increase in short-circuit current in venom-treated tissue that was similar to control values. These results show that scorpion venom mimics the mucosal effects of electrical activation of enteric neurons. These results suggest that a significant component of both scorpion venom action and the response to electrical field stimulation is mediated by neural release of acetylcholine, which activates epithelial muscarinic receptors.

scholarly journals Effect of tripropylsulfonium bromide on the contractile responses of the isolated guinea-pig ileum to some agonists

1990 ◽  
Vol 52 ◽  
pp. 352
Author(s):  
Shozo Takamura ◽  
Junko Yoshida ◽  
Shiro Suzuki ◽  
Fumihisa Miyoshi ◽  
Kenji Tokuno ◽  
...  
Keyword(s):  
Guinea Pig ◽  
Guinea Pig Ileum ◽  
Contractile Responses
Sign in / Sign up

Export Citation Format

Share Document