[Absorption kinetics of C14-GABA and its vitamin B conjugates in isolated bovine retina]. / Kinetyka pohlynannia izol'obanoiu sitkivkoiu byka 14C-GABA ta ïï kon'iuhativ z deiakymy vitaminamy hrupy B.

Absorption by the bovine retina of physiological concentration of PLP-GABA increase clearing 2-32 minutes of incubation in difference of GABA and its non metabolic preparations, which store up as much as possible in first minutes: picamilon > PLP-GABA > GABA > panthogam > biotinil-GABA. Kinetics of transport of GABA and its preparations into retina has a complex character. By the growth of concentration from 33 mM to 528 mM, it is linear for picamilion, showing diffusion, and not linear for GABA, PLP-GABA and panthogam, showing differently systems of its transport. And only GABA transport is activated by Na-ions.

[Distribution of 1-[14C] GABA and its conjugates with nicotinate, pyridoxal phosphate and biotin in tissues of guinea pigs in closed systems]. / Rozpodil [1-14C] GAMK ta ii kon'iugativ z nikotynatom, pitydoksalfosfatom i biotynom u tkanynakh morskykh svynok pry dii faktoriv zamknenoho prostoru.

Distribution of the total radioactive label in the blood, different parts of the brain (the whole cortex and its lobes, bulbi olfactorii, hippocamp, striopallidum, hypothalamus, thalamus, peduculi cerebri, cerebellum, pons, medulla oblongata), eye (retina, hyaloid and vascular membrane), hypophysis and liver of guinea pig males has been studied after the hypodermic injection of [14C] GABA and products of its conjugation with pyridoxal phosphate, nicotinic acid and biotin in the equimolar dose (50 nmol/g) under normal conditions and in case of action of the closed volume factors. Accumulation of the total label in the hypophysis after injection of [14C] GABA, PLP-[14C] GABA and nicotinoyl-[14C] GABA was 3.6, 3.1 and 2.7 times (respectively) as much as that in the blood. The content of the labelled compounds in the cortical structures of the telencephalon and in the diencephalon was the greatest in comparison with other parts of the brain. The permeability through a hemato-ophthalmic barrier was 3-5 times as much as that through a hemato-encephalic barrier. The closed volume factors lead to higher accumulation of the label as compared with the control after injection of [14C] GABA, PLP-[14C] GABA and biotinyl-[14C] GABA.

[The characteristics of the retinal absorption of labelled preparations of pikamilon and GABA]. / Osobennosti pogloshcheniia setchatkoi mechenykh preparatov pikamilona i GAMK.

The velocity of absorption of GABA and its derivative picamilon carbon-labelled by isolated bovine retina has been studied. It is shown that maximal velocity of GABA and picamilon absorption falls at the second incubation minute, then it decreases. In all the cases the picamilon absorption velocity is higher than the GABA absorption velocity. With an increase of concentration in the incubation medium of the labeled preparation under study the absorption velocity of GABA remains practically unchanged, while that of picamilon slightly increases.