TY - JOUR
T1 - Pharmacological comparison of the rat and guinea-pig cortical high affinity 5-hydroxytryptamine uptake system
AU - Hornsby, C. Diane
AU - Barnes, Janine M.
AU - Barnes, Nicholas M.
AU - Champaneria, Shashi
AU - Costall, Brenda
AU - Naylor, Robert J.
PY - 1992/4/15
Y1 - 1992/4/15
N2 - The pharmacological characteristics of the high affinity [3H]5-hydroxytryptamine ([3H]5-HT) uptake system were investigated in the cerebral cortex of the rat and guinea-pig. In crude cortical synaptosomal preparations from the rat and guinea-pig, [3H]5-HT accumulated with high affinity (Km, 72 ± 12 and 57 ± 14 nM for rat and guinea-pig cortical synaptosomal preparation, respectively, mean ± SEM, N = 5) and with a comparable maximum activity (Vmax, 1.22 ± 0.21 and 0.90 ± 0.19 pmol/min/mg protein for rat and guinea-pig corticol synaptosomal preparation, respectively, mean ± SEM, N = 5). Competition studies employing a range of structurally diverse competing compounds showed that the [3H]5-HT uptake was pharmacologically similar in both preparations. However, citalopram possessed approximately 10-fold weaker affinity to prevent [3H]5-HT uptake in the guinea-pig preparation when compared to the rat and all of the tricyclic antidepressants assessed in the present studies (amitriptyline, nortriptyline, desipramine and imipramine) displayed higher affinity in the guinea-pig preparation when compared to the rat. It is concluded that the high affinity 5-HT uptake systems in the rat and guinea-pig cortex are similar but may not be identical.
AB - The pharmacological characteristics of the high affinity [3H]5-hydroxytryptamine ([3H]5-HT) uptake system were investigated in the cerebral cortex of the rat and guinea-pig. In crude cortical synaptosomal preparations from the rat and guinea-pig, [3H]5-HT accumulated with high affinity (Km, 72 ± 12 and 57 ± 14 nM for rat and guinea-pig cortical synaptosomal preparation, respectively, mean ± SEM, N = 5) and with a comparable maximum activity (Vmax, 1.22 ± 0.21 and 0.90 ± 0.19 pmol/min/mg protein for rat and guinea-pig corticol synaptosomal preparation, respectively, mean ± SEM, N = 5). Competition studies employing a range of structurally diverse competing compounds showed that the [3H]5-HT uptake was pharmacologically similar in both preparations. However, citalopram possessed approximately 10-fold weaker affinity to prevent [3H]5-HT uptake in the guinea-pig preparation when compared to the rat and all of the tricyclic antidepressants assessed in the present studies (amitriptyline, nortriptyline, desipramine and imipramine) displayed higher affinity in the guinea-pig preparation when compared to the rat. It is concluded that the high affinity 5-HT uptake systems in the rat and guinea-pig cortex are similar but may not be identical.
UR - https://www.scopus.com/pages/publications/0026576046
U2 - 10.1016/0006-2952(92)90723-V
DO - 10.1016/0006-2952(92)90723-V
M3 - Article
C2 - 1575779
AN - SCOPUS:0026576046
SN - 0006-2952
VL - 43
SP - 1865
EP - 1868
JO - Biochemical Pharmacology
JF - Biochemical Pharmacology
IS - 8
ER -