Long-term administration (for 22-27 consecutive days) of caffeine (20 mg/kg/day p.o) developed tolerance to this drug by upregulating the central GABAergic activity. Development of Ehrlich ascites carcinoma (EAC) cell induced the whole brain GABAergic activity. But pretreatment of caffeine and continuation of its treatment in the course of development of EAC cells restored the EAC cell-induced change of GABAergic activity to control values. Thus, it may be concluded that caffeine (adenosine receptor antagonist) suppresses the EAC cell-induced induction of whole brain GABAergic activity in mice.

S MUKHOPADHYAY

M K PODDAR

University of Calcutta (informally known as Calcutta University or CU) is a collegiate public state university located in Kolkata, West Bengal, India.&nbsp;Within India it is recognized as a &quot;Five-Star University&quot; and accredited &quot;A&quot; Grade by National Assessment and Accreditation Council.

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The University of Calcutta has secured the Fifth position among the Universities of India in the prestigious &quot;Indian University Ranking 2019&quot; list, released by the NIRF of the Ministry of Human Resource Development, Government of India.

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It was established on 24 January 1857, and was one of the first institutions in Asia to be established as a multidisciplinary and Western-style university. Its alumni and faculty include several heads of state, heads of government, social reformers, prominent artists, only academy award winner and Dirac medal winner in India, many Fellows of the Royal Society and five Nobel laureates as of 2019 which is highest in South Asia.

University Of Calcutta

Long-term caffeine inhibits Ehrlich ascites carcinoma cell-induced induction of central GABAergic activity.

Neurochemical Research

Caffeine (10 or 20 mg/kg per day, po)-induced stimulation of locomotor activity (LA) reached its peak following 4 consecutive days of caffeine administration. Caffeine-induced stimulation of LA was restored to the control values following caffeine tolerance apter 16 or 12 consecutive days of caffeine treatment at a dose of 10 or 20 mg/kg per day, pp. Biochemical studies showed that caffeine in the nontolerant condition reduced GABAergic activity in cerebral cortex, corpus striatum, cerebellum, hypothalamus and pons-medulla; but tolerance to caffeine (10 or 20 mg/kg per day, po) pushed up the GABAergic activity to the control value in all these regions of brain. Further, it was found that muscimol reduced the LA while bicuculline stimulated LA in the caffeine tolerant condition. Thus, from the present study it may be concluded that: (a) caffeine-induced stimulation of LA is dependent on dose and duration of caffeine treatment, (b) development of tolerance to caffeine is dependent on the dosage of caffeine, and (c) the reduction of central GABAergic activity in the caffeine-nontolerant condition pushed up and restored the LA to the control level on the development of tolerance to caffeine.

Is GABA involved in the development of caffeine tolerance?

Cancer Letters

Differential expression of adenosine A1 receptors in colorectal cancer and related mucosa

Experimental Brain Research

Sex differences in GABA/benzodiazepine receptor changes and corticosterone release after acute stress in rats

NeuroReport

Inhibition of a gamma aminobutyric acid A receptor by caffeine

British Journal of Pharmacology

Caffeine and related compounds block inhibitory amino acid-gated Cl− currents in freshly dissociated rat hippocampal neurones

Long-term caffeine inhibits Ehrlich ascites carcinoma cell-induced induction of central GABAergic activity

Journal	Neurochemical Research
Publisher	KLUWER ACADEMIC/PLENUM PUBL
ISSN	0364-3190