Effect of GABA on Melatonin Content in Golden Hamster Retina

Jaliffa, Carolina O.; Faillace, María Paula; Lacoste, Francisco Firpo; Llomovatte, Diego Weinberg; Sarmiento, María I. Keller; Rosenstein, Ruth E.

doi:10.1046/j.1471-4159.1999.0721999.x

Cited by 15 publications

(12 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Furthermore, GABA increases melatonin content in a dose-dependent manner in the hamster retina [93]. Our results suggest that GABA could, through membrane hyperpolarization and activation of casein kinase, stimulate the degradation of accumulated PER proteins on the falling phase of their rhythm (which roughly corresponds to the night state), acting to remove feedback inhibition on Per transcription and thereby preparing retinal oscillators for transcriptional activation that characterizes the “day” state.…”

Section: Discussionmentioning

confidence: 90%

An Autonomous Circadian Clock in the Inner Mouse Retina Regulated by Dopamine and GABA

et al. 2008

View full text Add to dashboard Cite

The influence of the mammalian retinal circadian clock on retinal physiology and function is widely recognized, yet the cellular elements and neural regulation of retinal circadian pacemaking remain unclear due to the challenge of long-term culture of adult mammalian retina and the lack of an ideal experimental measure of the retinal circadian clock. In the current study, we developed a protocol for long-term culture of intact mouse retinas, which allows retinal circadian rhythms to be monitored in real time as luminescence rhythms from a PERIOD2::LUCIFERASE (PER2::LUC) clock gene reporter. With this in vitro assay, we studied the characteristics and location within the retina of circadian PER2::LUC rhythms, the influence of major retinal neurotransmitters, and the resetting of the retinal circadian clock by light. Retinal PER2::LUC rhythms were routinely measured from whole-mount retinal explants for 10 d and for up to 30 d. Imaging of vertical retinal slices demonstrated that the rhythmic luminescence signals were concentrated in the inner nuclear layer. Interruption of cell communication via the major neurotransmitter systems of photoreceptors and ganglion cells (melatonin and glutamate) and the inner nuclear layer (dopamine, acetylcholine, GABA, glycine, and glutamate) did not disrupt generation of retinal circadian PER2::LUC rhythms, nor did interruption of intercellular communication through sodium-dependent action potentials or connexin 36 (cx36)-containing gap junctions, indicating that PER2::LUC rhythms generation in the inner nuclear layer is likely cell autonomous. However, dopamine, acting through D1 receptors, and GABA, acting through membrane hyperpolarization and casein kinase, set the phase and amplitude of retinal PER2::LUC rhythms, respectively. Light pulses reset the phase of the in vitro retinal oscillator and dopamine D1 receptor antagonists attenuated these phase shifts. Thus, dopamine and GABA act at the molecular level of PER proteins to play key roles in the organization of the retinal circadian clock.

show abstract

Section: Discussionmentioning

confidence: 90%

An Autonomous Circadian Clock in the Inner Mouse Retina Regulated by Dopamine and GABA

et al. 2008

View full text Add to dashboard Cite

show abstract

“…Previous studies have shown that levels of retinal melatonin are partially regulated by dopamine that acts through a D4 receptor (Jaliffa et al, 2000;Tosini and Dirden, 2000). D4 receptors are negatively coupled with adenylyl cyclase (i.e., their activation decreases the activity of adenlylyl cyclase and thus the levels of cAMP) and therefore is likely that the D4 receptors present in the pineal are also involved in the regulation of pineal melatonin levels.…”

Section: Discussionmentioning

confidence: 99%

Analysis of daily and circadian gene expression in the rat pineal gland

Fukuhara¹,

Tosini²

2008

Neuroscience Research

View full text Add to dashboard Cite

The mammalian pineal gland is an important component of the circadian system. In the present study, we examined the expression of roughly 8000 genes in the rat pineal gland as a function of time of day under light-dark (LD) cycles and in constant dark (DD) using oligo DNA microarray technique. We identified 47 and 13 genes that showed higher levels at night and day, respectively, under LD. The same patterns of expression were also observed in DD. About half of the genes that peaked at night have a known biological function, i.e., transcription factors and proteins that are involved in signaling cascades, whereas 14 are expressed sequence tags and 8 have an unknown biological function. Twelve of the genes that are up-regulated at night were also up-regulated after 1 h NE stimulation, thus suggesting that the expression of these genes is controlled by adrenergic mechanisms. Of the 13 genes that were up-regulated in the daytime, 6 coded for proteins that are involved in intracellular signaling pathways. The results obtained with microarray analysis were well correlated with data obtained using real time quantitative RT-PCR. The present results provide new materials to dissect and understand the pineal physiology.

show abstract

“…Many relevant retinal parameters such as GABA (Jaliffa et al 2001), dopamine (Jaliffa et al 2000) and melatonin levels (Faillace et al 1994;Tosini and Menaker 1996) among many others, significantly fluctuate according the time of the day, even under constant lighting conditions, supporting the existence of a retinal circadian clock. However, the cellular location (or possibly multiple locations) of the retinal circadian clock(s) has not been fully identified yet.…”

Section: Discussionmentioning

confidence: 99%

“…Many relevant retinal parameters such as GABA (Jaliffa et al. 2001), dopamine (Jaliffa et al. 2000) and melatonin levels (Faillace et al.…”

Section: Discussionmentioning

confidence: 99%

Circadian variations of prostaglandin E2 and F2 α release in the golden hamster retina

Zavalía

Fernandez

Sande

et al. 2010

Journal of Neurochemistry

Self Cite

View full text Add to dashboard Cite

Circadian variations of prostaglandin E2 and F2a release were examined in the golden hamster retina. Both parameters showed significant diurnal variations with maximal values at midnight. When hamsters were placed under constant darkness for 48 h, the differences in prostaglandin release between subjective mid-day and subjective midnight persisted. Western blot analysis showed that cyclooxygenase (COX)-1 levels were significantly higher at midnight than at mid-day, and at subjective midnight than at subjective mid-day, whereas no changes in COX-2 levels were observed among these time points. Immunohistochemical studies indicated the presence of COX-1 and COX-2 in the inner (but not outer) retina. Circadian variations of retinal prostaglandin release were also assessed in suprachiasmatic nuclei (SCN)-lesioned animals. Significant differences in retinal prostaglandin release between subjective mid-day and subjective midnight were observed in SCN-lesioned animals. These results indicate that hamster retinal prostaglandin release is regulated by a retinal circadian clock independent from the SCN. Thus, the present results suggest that the prostaglandin/COX-1 system could be a retinal clock output or part of the retinal clock mechanism.

show abstract

Effect of GABA on Melatonin Content in Golden Hamster Retina

Cited by 15 publications

References 38 publications

An Autonomous Circadian Clock in the Inner Mouse Retina Regulated by Dopamine and GABA

An Autonomous Circadian Clock in the Inner Mouse Retina Regulated by Dopamine and GABA

Analysis of daily and circadian gene expression in the rat pineal gland

Circadian variations of prostaglandin E2 and F2 α release in the golden hamster retina

Contact Info

Product

Resources

About