İntraserebroventriküler olarak uygulanan Exendin-(9-39) santral "Glucagon-like peptide-1"in kardiyovasküler etkilerini önler mi?

Bu çalışmada uyanık, serbestçe hareket edebilen sıçanlara İntraserebroventriküler (i.c.v.) olarak enjekte edilen "glucagon-like peptide-1" (GLP-l)'in kan basıncı ve kalp hızı üzerine olan etkileri ve bu etkilerine santral spesifik reseptörlerinin aracılık edip etmediğinin belirlenmesi amaçlandı. Deneylerde kullanılan erkek Wistar albino sıçanlara eter anestezisi altında, sağ femoral artere kateter ve i.c.v. enjeksiyonlar,için sağ lateral ventriküle kanül yerleştirildi. Arteriyel kan basıncı ve kalp hızı, "TDA96 Transducer Data Acquisition System" aracılığıyla kaydedildi. Sıçanların ilaç enjeksiyonlarından önce ve enjeksiyonları takiben 30 dakika süresince kan basınçları ve kalp hızlan kaydedildi. İ.c.v. yolla verilen GLP-I (100, 500 ve 1000 ng/10$mu$l) kan basıncı ve kalp hızında doza bağlı olarak artış oluşturdu. GLP-I'in bu etkilerini i.c.v. olarak enjekte edilen reseptör antagonisti exendin-(9-39) (2500ng/10 $mu$l) inhibe etti. Bulgularımız i.c.v. GLP-I'in kan basıncı ve kalp hızını yükselttiğini, bu etkilerine santral spesifik reseptörlerinin aracılık ettiğini göstermektedir.

Does intracerebroventricularly-injected Exendin-(9-39) prevent the cardiovascular effects of central glucagon-like peptide-17

In this study, we aimed to investigate the effects of intracerebroventricularly (i.c.v.)-injected glucagon-like peptide-1 (GLP-I) on blood pressures and heart rates of conscious, freely-moving rats, and whether specific receptors mediate these effects. Male Wistar albino rats used throughout the experiments were implanted with a cathether through the right femoral artery and with a cannula into the right lateral ventricle for i.c.v. injections, under ether anesthesia. Blood pressure and heart rate were recorded by a "TDA96 Transducer DataAcquisi-tion System". Blood pressures and heart rates of rats were observed before and for 30 minutes following drug injections. I.c.v. GLP-I (100, 500 and 1000 ng/10 $mu$l) caused a dose-dependent increase in both blood pressure and heart rate. The effects of GLP-I on blood pressure and heart rate were inhibited by i.c.v. receptor antagonist exendin-(9-39) (2500 ng/$mu$l). Our data indicate that i.c.v. GLP-I in-creases blood pressure and heart rate, and that activation of central specific receptors mediate these effects.

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