SESSION: Depression

Involvement of cerebral �1-adrenergic receptors in

responsiveness to chronic mild stress and imipramine treatment

Adam Bielawski1, Marta Kowalska1, Katarzyna Rafa-Zab³ocka1, Mariusz Papp2,Irena Nalepa1

�Department of Brain Biochemistry, �Laboratory of Behavioral Pharmacology, Department of Pharmacology, Instituteof Pharmacology, Polish Academy of Sciences, Smêtna 12, PL 31-343 Kraków, Poland

We investigated how the chronic mild stress (CMS)

procedure that induces depression-like symptoms (an-

hedonia) in rodents affects the �1-ARs and whether

imipramine interferes with the CMS-induced effects

at the level of receptors’ expression. Rats were sub-

jected to either 3-weeks or 8-weeks CMS and were

given imipramine (IMI) for five weeks. The total

�1-AR density was analyzed by [�H]prazosin autora-

diography and mRNA expression of their �1A, �1B,

and �1D subtypes was measured by RT-qPCR. In the

hippocampus of CMS-reactive rats the mRNA expres-

sion of only �1B was increased after 3-weeks-CMS

(vs. sham and stress-nonreactive groups). In rats sub-

jected to 8-weeks CMS that did not respond to IMI

treatment, the expression of �1A-, �1B- and �1D-AR

mRNAs was increased (vs. sham-sal and stress-IMI

groups). Similar direction of changes was seen in the

�1-AR density.

Opposite change was found in the thalamus of

CMS reactive rats where the �1B and other two re-

ceptor subtypes (�1A and �1D) mRNA were de-

creased (vs. sham and stress-nonreactive rats) and

�1-AR total density was attenuated as well. In rats re-

sponding to IMI the mRNA expression of only �1A

was increased whereas there was no change in the re-

ceptors of IMI-non-responders,

Our results suggest that �1-ARs play a role in me-

diating the behavioral effects of CMS. All subtypes of

hippocampal �1-AR are importantly involved in the

phenomenon of resistance of depressive rats to IMI

treatment and the �1B-AR seems to be specifically

engaged in responsiveness to CMS action.

Acknowledgments:

Supported by statutory funds of the Institute of Pharmacology and

POIG.01.01.02-12-004/09-00 financed by European Regional

Development Fund.

Hormonal, metabolic and behavioral consequences of prenatal

stress

Jan Detka, Anna Kurek, Katarzyna G³ombik, Monika Leœkiewicz,Agnieszka Basta-Kaim, Marta Kubera, W³adys³aw Lasoñ, Bogus³awa Budziszewska

Department of Experimental Neuroendocrinology, Institute of Pharmacology, Polish Academy of Sciences, Smêtna 12,PL 31-343 Kraków, Poland

A high prevalence of depression in patients with dia-

betes suggests the involvement of similar factor/s in

pathogenesis of these disorders. Since both depression

and hyperglycemia are often accompanied by hyper-

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