The Effects of Constant Darkness and Constant  Light on the Pineal Gland and Thymus  Morphology in the Rats

Nihal İÇTEN

Makale detayları

The Effects of Constant Darkness and Constant Light on the Pineal Gland and Thymus Morphology in the Rats

Yazarlar:

Nihal İÇTEN

Yayıncı:

TUBITAK

Dergi:

Turkish Journal of Medical Sciences 1998 Vol.28 Issue 1, pp.7-12

Belge Tipi:

Makale

Yayın Tarihi:

12/1997

Belge Dili:

Türkçe

Document ID (Org No.):

2000758478

Sıklık:

İki Aylık

eISSN:

1303-6165

pISSN:

1300-0144

Anahtar kelimeler:

Özet:

 

It is known that periods of constant  darkness and constant light cause stim-ulation  and inhibition of melatonin secretion  from the pineal gland. It is also suggested  that neuroendocrine responses to environmental  stimuli, such as light, can influence  immune responses through the pineal gland.  For these reasons, in this study the effects of  the alterations in the photoperiod rhythm on  the pineal gland and thymus morphology  were experimentally investigated.  30 Swiss albino rats, aged 4 wk, were divided  into 3 groups. Group I rats were kept  in a dark room, group II in a room under a  bright artificial light and group III (control)  animals were exposed to a 12:12 h light:  dark cycle. All animals were killed after 5 wk.  Overall body weight was not affected by the  dark or light periods. In group I, the thymus  weight increased by 38%, the increase in the  thymus cortex thickness was 34.5%. In  group II, the thymus weight decreased by  21% and the decrease in the thymus cortex  thickness was 18%. The differences among  groups in the thymus weight and the thymus  cortex thickness were found statistically significant.  In differences in the diameter of the pineal  gland and the pineal cell number of the darkness  group and the light group according to  the control group was not found statistically  significant. However, the differences in he  diameter of he pinealocyte nuclei among the  groups were statistically significant. These  findings point out that the changes in the periods  of darkness and light have effects on  the pineal gland and immune system.

 

It is known that periods of constant  darkness and constant light cause stim-ulation  and inhibition of melatonin secretion  from the pineal gland. It is also suggested  that neuroendocrine responses to environmental  stimuli, such as light, can influence  immune responses through the pineal gland.  For these reasons, in this study the effects of  the alterations in the photoperiod rhythm on  the pineal gland and thymus morphology  were experimentally investigated.  30 Swiss albino rats, aged 4 wk, were divided  into 3 groups. Group I rats were kept  in a dark room, group II in a room under a  bright artificial light and group III (control)  animals were exposed to a 12:12 h light:  dark cycle. All animals were killed after 5 wk.  Overall body weight was not affected by the  dark or light periods. In group I, the thymus  weight increased by 38%, the increase in the  thymus cortex thickness was 34.5%. In  group II, the thymus weight decreased by  21% and the decrease in the thymus cortex  thickness was 18%. The differences among  groups in the thymus weight and the thymus  cortex thickness were found statistically significant.  In differences in the diameter of the pineal  gland and the pineal cell number of the darkness  group and the light group according to  the control group was not found statistically  significant. However, the differences in he  diameter of he pinealocyte nuclei among the  groups were statistically significant. These  findings point out that the changes in the periods  of darkness and light have effects on  the pineal gland and immune system.

Makale detayları

The Effects of Constant Darkness and Constant Light on the Pineal Gland and Thymus Morphology in the Rats

Yazarlar:

Nihal İÇTEN

Yayıncı:

TUBITAK

Dergi:

Turkish Journal of Medical Sciences 1998 Vol.28 Issue 1, pp.7-12

Belge Tipi:

Makale

Yayın Tarihi:

12/1997

Belge Dili:

Türkçe

Document ID (Org No.):

2000758478

Sıklık:

İki Aylık

eISSN:

1303-6165

pISSN:

1300-0144

Photoperiodicity

pineal gland

immune system

morphometry

rat.

Sayı

Makale detayları

The Effects of Constant Darkness and Constant Light on the Pineal Gland and Thymus Morphology in the Rats

Yazarlar: Nihal İÇTEN

Yayıncı: TUBITAK

Dergi: Turkish Journal of Medical Sciences 1998 Vol.28 Issue 1, pp.7-12

Belge Tipi: Makale

Yayın Tarihi: 12/1997

Belge Dili: Türkçe

Document ID (Org No.): 2000758478

Sıklık: İki Aylık

eISSN: 1303-6165

pISSN: 1300-0144

Photoperiodicity

pineal gland

immune system

morphometry

rat.

Sayı

Yazarlar:

Nihal İÇTEN

Yayıncı:

TUBITAK

Dergi:

Turkish Journal of Medical Sciences 1998 Vol.28 Issue 1, pp.7-12

Belge Tipi:

Makale

Yayın Tarihi:

12/1997

Belge Dili:

Türkçe

Document ID (Org No.):

2000758478

Sıklık:

İki Aylık

eISSN:

1303-6165

pISSN:

1300-0144