RESUMEN
The effects of cholecystokinin (CCK-8) and the CCK receptor antagonist proglumide, on antinociception induced by local peripheral (subcutaneous) injected morphine in non-diabetic (ND) and streptozotocin-induced diabetic (D) rats, were examined by means of the formalin test. Morphine induced dose-dependent antinociception both in ND and D rats. However, in D rats, antinociceptive morphine potency was about twofold less than in ND rats. Pre-treatment with CCK-8 abolished the antinociceptive effect of morphine in a dose-dependent manner in both groups of rats. Additionally, proglumide enhanced the antinociceptive effect induced by all doses of morphine tested. Both CCK-8 and proglumide had no effect on flinching behaviour when given alone to ND rats. Unlike ND rats, in D rats proglumide produced dose-dependent antinociception and CCK-8 enhanced formalin-evoked flinches, as observed during the second phase of the test. In conclusion, our data show a decrease in peripheral antinociceptive potency of morphine when diabetes was present. Additionally, peripheral CCK plays an antagonic role to the peripheral antinociceptive effect of morphine, additional to the well known CCK/morphine interaction at spinal and supraspinal level.
Asunto(s)
Colecistoquinina/metabolismo , Morfina/uso terapéutico , Narcóticos/uso terapéutico , Neuralgia/tratamiento farmacológico , Animales , Área Bajo la Curva , Colecistoquinina/administración & dosificación , Colecistoquinina/antagonistas & inhibidores , Diabetes Mellitus Experimental/complicaciones , Relación Dosis-Respuesta a Droga , Interacciones Farmacológicas , Formaldehído/efectos adversos , Masculino , Neuralgia/etiología , Dimensión del Dolor , Umbral del Dolor/efectos de los fármacos , Fragmentos de Péptidos/administración & dosificación , Proglumida/administración & dosificación , Ratas , Ratas WistarRESUMEN
The present study investigated the effects of bilateral injections of the nonselective CCK receptor antagonist proglumide or CCK-8 into the lateral parabrachial nuclei (LPBN) on the ingestion of 0.3 M NaCl and water induced by intracerebroventricular injection of ANG II or by a combined treatment with subcutaneous furosemide (Furo) + captopril (Cap). Compared with the injection of saline (vehicle), bilateral LPBN injections of proglumide (50 micrograms . 200 nl-1 . site-1) increased the intake of 0.3 M NaCl induced by intracerebroventricular ANG II (50 ng/1 microliter). Bilateral injections of proglumide into the LPBN also increased ANG II-induced water intake when NaCl was simultaneously available, but not when only water was present. Similarly, the ingestion of 0.3 M NaCl and water induced by the treatment with Furo (10 mg/kg) + Cap (5 mg/kg) was increased by bilateral LPBN proglumide pretreatment. Bilateral CCK-8 (0.5 microgram . 200 nl-1 . site-1) injections into the LPBN did not change Furo + Cap-induced 0.3 M NaCl intake but reduced water consumption. When only water was available after intracerebroventricular ANG II, bilateral LPBN injections of proglumide or CCK-8 had no effect or significantly reduced water intake compared with LPBN vehicle-treated rats. Taken together, these results suggest that CCK actions in the LPBN play a modulatory role on the control of NaCl and water intake induced by experimental treatments that induce hypovolemia and/or hypotension or that mimic those states.
Asunto(s)
Apetito/fisiología , Colecistoquinina/fisiología , Rombencéfalo/fisiología , Animales , Depresores del Apetito/administración & dosificación , Colecistoquinina/antagonistas & inhibidores , Inyecciones Intraventriculares , Masculino , Proglumida/administración & dosificación , Ratas , Ratas Sprague-Dawley , Receptores de Colecistoquinina/antagonistas & inhibidores , Receptores de Colecistoquinina/fisiología , Rombencéfalo/efectos de los fármacos , Sincalida/administración & dosificación , Cloruro de Sodio , AguaRESUMEN
Con la finalidad de evaluar la utilidad de usar una mezcla a dosis constantes (250 mg de xilazina + 100 mg de keatmina/animal) para inmovilizar venados cola blanca (Odocoileus virginianus), se utlizó un rifle "Dist-Inyect" calibre 32 con adaptador de cargas explosivas 22 para proyectar el dardo vector de la mezcla de drogas. Después de una inyección por vía intramuscular (IM), se logró inmovilizar 5 animales entre los 6 min. y 37 min. (prom. 28 min).Con la aplicación por vía endovenosa de 0,1-02 mg. de sulfato de atropina/Kg. de peso corporal, los venados se recuperaron satisfactoriamente entre los 89 min. y 150 min. Tomando como base las ventajas expuestas en el trabajo, se conclute que aún a concentraciones bajas constantes, la mezcla es sumamente útil, confiable y segura para inmovilizar venados silvestres. Para mejorar la técnica se recomienda aumentar en un 20 por ciento la concentración de ambas drogas y usar clorhidrato de yohimbina como antídoto