[Tensiometric study of muscular strips of guinea pig gallbladder].
The tensiometric properties of smooth muscle strips from 10 male guinea pig gallbladders were evaluated following acetylcholine (ACH), cholecystokinin octapeptide (CCK-OP), cerulein (CRL) and histamine (HIS) administration. All agonists induced dose-dependent tonic contractions with the maximum effect caused by the octapeptide. CRL showed a 9-folds higher relative potency when compared to CCK-OP. ED50s of agonists were: ACH 1.36 +/- 0.28 SEM microM (n = 14; range 0.20-3.60); HIST, 5.7 +/- 1.9 microM (n = 12; range 1-23); CRL 0.72 +/- 0.15 nM (n = 8; range 0.35-1.07); CCK-OP, 6.77 +/- 1.80 nM (n = 12; range 0.44-20.32); For the same strips, max tension (g), was: 1.97 (SEM 0.12) for ACH; 1.5 (0.18) for HIST; 1.81 (0.18) for CRL; 2.44 (0.14) for CCK-OP. Pretreatment of the strips with atropine (1 microM) completely abolished ACh-induced contractions, without affecting either CCK-OP or CRL responses. The model represents a valid "in vitro" study of different molecules whose action might stimulate, enhance or inhibit the physiological hormonal and non-hormonal effect of the agonists at the level of animal and human gallbladder smooth muscle.
Portincasa
P
P
Brandonisio
R
R
Palma
A
A
Palasciano
G
G
D000109:Acetylcholine / Q000502:physiology; D000818:Animals; D002108:Ceruletide / Q000502:physiology; D005704:Gallbladder / Q000502:physiology*; D006168:Guinea Pigs; D006632:Histamine / Q000502:physiology; D008297:Male; D009119:Muscle Contraction; D012844:Sincalide / Q000502:physiology
D006632:Histamine; D002108:Ceruletide; D012844:Sincalide; D000109:Acetylcholine
Studio tensiometrico su strisce muscolari di colecisti di cavia.