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UTICAJ EKSTREMNIH USLOVA SPOLJAŠNJE TEMPERATURE NA KOLIĈINU GALANINA
U HIPOTALAMUSU, HIPOFIZI I SERUMU PACOVA

INFLUENCE OF EXTREME CONDITIONS OF EXTERNAL TEMPERATURE ON THE AMOUNT
OF GALANIN IN HYPOTHALAMUS, PITUITARY GLAND AND SERUM OF RATS

AUTOR: TAMARA RAKIĆ, učenica III razreda Šeste beogradske gimnazije, Regionalni centar za talente Beograd
II MENTOR: Dr NEBOJŠA JASNIĆ, docent, Biološki fakultet, Univerzitet u Beogradu

REZIME

Danas najprihvadenija, Goldštajnova teorija o stresu, govori da se radi uspostavljanja homeostaze u
organizmu aktiviraju različiti sistemi, u zavisnosti od tipa stresora, same jedinke i okolnosti. Alostaza je
proces dinamičkog održavanja homeostaze unutar nekog opsega vrednosti odreĎenih fizioloških
parametara i ako je organizam dugoročno izložen stresu, može nastati alostatičko preopteredenje.
Stresori su stimulusi koji remete homeostazu i oni mogu biti fizički, psihološki, socijalni i stresori koji
remete kardiovaskularnu i metaboličku homeostazu. Galanin je protein koji ima ulogu u regulaciji
fizioloških sistema koji odgovaraju na stres, kao i u mnogim drugim biološkim i fiziološkim funkcijama. On
se kod vedine sisara sastoji od 29 aminokiselina, a kod ljudi od 30. U galaninsku porodicu spadaju i
preprogalanin, GMAP, GALP i alarin. Postoje tri receptora za galanin – GalR1, GalR2 i GalR3. U ovom radu
je ispitivana uloga galanina pri odgovoru na izlaganje termičkim stresorima različitog trajanja. Analizirani
su uzorci hipotalamusa, hipofize i seruma pacova izlaganih niskoj (+4˚C u trajanju od 30 min i +4˚C u
trajanju od 60 min) i visokoj temperaturi (+38˚C u trajanju od 60 min). UtvrĎeno je da u uzorcima galanin
nije prisutan u očekivanoj formi (molekulske mase ~13 kDa), ved u formama od ~21 kDa i ~35 kDa, za
koje se smatra da su GMAP i preprogalanin u stadijumu obrade respektivno. KLJUČNE REČI: galanin,
preprogalanin, GMAP, hipotalamus, hipofiza, serum, termički stresori

SUMMARY

Today the most widely accepted theory of stress, Goldstein’s theory, states that different systems are
activated in the organism for the sake of establishing homeostasis depending on the type of the stressor,
the individual itself and the environment. Allostasis is the process of dynamic maintenance of
homeostasis inside a range of specific physiological parameters and if the organism is overly exposed to
stress, allostatic overload may occur. Stressors are stimuli that disrupt homeostasis and they can be
physical, psychological, social and stressors that disrupt cardiovascular and metabolic homeostasis.
Galanin is a protein that has a role in regulation of physiological systems that answer to stress, as well as
in many other biological and physiological functions. It is in most mammals made up of 29 amino acids,
in humans of 30 amino acids. In the galanin family preprogalanin, GMAP, GALP and alarin, are also
classified. There are three galanin receptors – GalR1, GalR2 and GalR3. In this work the role of galanin in
the answer to thermic stressors of varied durations has been tested. Samples of hypothalamus, pituitary
gland and serum tissues of rats exposed to low (+4˚C during a 30 min period and +4˚C during a 60 min
period) and high temperatures (+38˚C during a 60 min period) have been analyzed. It has been
established that in the samples galanin is not present in its expected form (with the mass of ~13 kDa),
but rather in the forms of ~21 kDa and ~35 kDa. It is assumed that they represent GMAP and
preprogalanin in a processing stadium respectively.

KEY WORDS: galanin, preprogalanin, GMAP, hypothalamus, pituitary gland, serum, thermic stressors