𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Adenosine 3′∶5′-cyclic monophosphate mediates a 5-hydroxytryptamine-induced response in neonatal rat motoneurones

✍ Scribed by P. M. Larkman; J. S. Kelly; T. Takahashi

Publisher
Springer
Year
1995
Tongue
English
Weight
729 KB
Volume
430
Category
Article
ISSN
0031-6768

No coin nor oath required. For personal study only.

✦ Synopsis

5-Hydroxytryptamine (5-HT) is present in nerve fibres descending from the brainstem Raphe nuclei to motoneurones and its release is thought to exert excitatory actions. 5-HT, applied from the outside, directly depolarizes spinal and cranial motoneurones in slices. This action of 5-HT is mediated, in part, by an inwardly rectifying cationic current, Ih. In cardiac cells, an equivalent current, if, has been shown to be directly activated by adenosine 3': Y-cyclic monophosphate (cAMP) applied to the inside of the patch membrane. By applying the whole-cell method to thin slices of brainstem and spinal cord, we have shown that intracellularly applied cAMP and extracellularly applied dibutyryl cAMP or forskolin mimics the inward current induced by 5-HT. The selective cAMP phosphodiesterase inhibitor, Ro 20-1724, clearly prolonged the 5-HT-induced current. Maximal doses of dibutyryl cAMP or forskolin occluded the 5-HTinduced current. The broad spectrum protein kinase inhibitors 1-(5-isoquinolinesulphonyl)-2-methlypiperazine (H-7) and N-[2-(methylamino)ethyl]-5-isoquinolinesulphonamide (H-8) had no effect on the currents induced by 5-HT and forskolin. From these results, we suggest that activation of 5-HT receptors on the motoneuronal membrane stimulates formation of intracellular cAMP, thereby inducing the inward current, possibly by a direct action on Ih.

📜 SIMILAR VOLUMES

Norepinephrine and cyclic adenosine 3′:5
Norepinephrine and cyclic adenosine 3′:5′-cyclic monophosphate enhance a nifedipine-sensitive calcium current in cultured rat astrocytes
✍ Dr. B. A. MacVicar; F. W. Y. Tse 📂 Article 📅 1988 🏛 John Wiley and Sons 🌐 English ⚖ 731 KB

We employed two microelectrode current-clamp and voltage-clamp methods to examine the modulation of C a + + channels by norepinephrine and cyclic AMP (CAMP) in cultured astrocytes from the rat cerebral cortex. Currents owing to Cat+ channels were maximized by replacing Ca++ with Ba+ + in the extrace

Characteristic behavioral alterations in
Characteristic behavioral alterations in rats induced by rolipram and other selective adenosine cyclic 3′,5′-monophosphate phosphodiesterase inhibitors
✍ Helmut Wachtel 📂 Article 📅 1982 🏛 Springer 🌐 English ⚖ 887 KB

The significance of a characteristic symptomatology (hypothermia, hypoactivity, forepaw shaking, grooming, head twitches) as a potential in vivo correlate of enhanced availability of brain adenosine cyclic 3',5'-monophosphate (cAMP) was examined in rats following systemic administration of various d

Mechanism of the impairment of the gluca
Mechanism of the impairment of the glucagon-stimulated phosphoenolpyruvate carboxykinase gene expression by interleukin-6 in rat hepatocytes: Inhibition of the increase in cyclic 3′,5′ adenosine monophosphate and the downstream cyclic 3′,5′ adenosine monophosphate action
✍ B Christ; A Nath; K Jungermann 📂 Article 📅 1997 🏛 John Wiley and Sons 🌐 English ⚖ 262 KB

ferase reporter gene construct under the control of a PCK In cultured rat hepatocytes, the gluconeogenic key enzyme, phosphoenolpyruvate carboxykinase (PCK), is induced by gene promoter fragment (base 0979 to base /32). Luciferase activity was determined after stimulation of the cells with glucagon