Wyniki wyszukiwania

1

Niepamięć operacyjna

100%

Orser B. A.

Świat Nauki

|

2007

|

nr 07

2

Neuroprzekaznik hamujacy w plastycznosci kory mozgu

80%

Siucinska E.

Kosmos

|

2005

|

tom 54

|

nr 2-3

195-212

3

Ekspresja genu GnRH i genu receptora GnRH (GnRHR) w układzie podwzgórzowo-przysadkowym owcy w różnych stanach fizjologicznych

80%

Ciechanowska M., Lapot M., Malewski T., Mateusiak K., Misztal T., Przekop F.

Postępy Nauk Rolniczych

|

2010

|

tom 62

|

nr 4

4

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Neuralna regulacja uwalniania gonadoliberyny u owcy w roznych stanach fizjologicznych; rola receptorow GABA-A

80%

Tomaszewska-Zaremba D., Mateusiak K., Przekop F.

Postępy Nauk Rolniczych

|

2005

|

tom 52

|

nr 5

7-16

One of the most important inhibitory neurotransmitter in the control of gonadoliberin (GnRH) secretion is gamma-aminobutyric acid (GABA). To examine the role of GABAA receptor mediating systems in the control of GnRH/LH release from the preoptic area and ventromedial hypothalamus of ewes in different reproductive stages (seasonal anestrus, follicular and luteal phase of the estrous cycle) the extracellular concentration of GnRH, ß-endorphin, noradrenaline, dopamine and metabolites of catecholamines: MHPG, DOPAC were quantified during local stimulation or blockade of GABAA receptors with muscimol or bicuculline, respectively. Stimulation of GABAA receptors in the preoptic area and ventromedial hypothalamus markedly attenuatted GnRH/LH release in the anestrous ewes and in sheep during follicular phase of the estrous cycle but did not affect these hormones secretion in animals during the luteal phase of the estrous cycle. The activation of GABAA receptors in these structures in different way affected ß-endorphinergic and catecholaininergic system activity in anestrous ewes arid animals during the follicular phase; lack of changes in the release of ß-endorphin, noradrenaline and dopamine was noted in ewes during the luteal phase. With the exception of preoptic area in anestrous ewes the blockade of GABAA receptors in the preoptic and ventromedial hypothalamus affected in specifical way the activity of ß-endorphinergic and catecholaminergic systems in these structure in all animals. In conclusion: presented results indicate that activation of GABAA receptors in the preoptic area and ventromedial hypothalamus of anestrous ewes and sheep during follicular phase of the estrous cycle inhibits GnRH/LH secretion. Presented results indicate that different neural mechanisms may be involved in the suppression of GnRH/LH by GABA directly through the GABAA receptor mechanism on the perikaria or on the axon terminals of GnRH cells, and/or indirectly through GABAA receptor processes on ß-endorphinergic and catecholaminergic systems. Lack of changes in GnRH/LH release during GABAA receptor activation in ewes during luteal phase of the estrous cycle indicates that the influence of GABA on GnRH-ergic activity depends on physiological state of animals. Blockade of GABAA receptors in the anestrous and cycling ewes does not change GnRH/LH release; it is suggested that blockade of GABAA recreceptors may change GnRH neurons response to ß-endorphin and dopamine.

5

Prosze liczyc do dziesieciu

60%

Melton L.

Świat Nauki

|

2002

|

nr 04

10-11

Ograniczanie wyników

2 Postępy Nauk Rolniczych

2 Świat Nauki

1 Kosmos

2 Mateusiak K.

2 Przekop F.

1 Ciechanowska M.

1 Lapot M.

1 Malewski T.

1 Melton L.

1 Misztal T.

1 Orser B. A.

1 Siucinska E.

1 Tomaszewska-Zaremba D.

1 2010

1 2007

2 2005

1 2002

Niepamięć operacyjna

Neuroprzekaznik hamujacy w plastycznosci kory mozgu

Ekspresja genu GnRH i genu receptora GnRH (GnRHR) w układzie podwzgórzowo-przysadkowym owcy w różnych stanach fizjologicznych

Neuralna regulacja uwalniania gonadoliberyny u owcy w roznych stanach fizjologicznych; rola receptorow GABA-A

Prosze liczyc do dziesieciu