6533b82dfe1ef96bd12909e6

RESEARCH PRODUCT

Correlation of the number of pineal ?synaptic? ribbons and spherules with the level of serum melatonin over a 24-hour period in male rabbits

H. A. WelkerF. Martinez SorianoLutz Vollrath

subject

Maleendocrine systemmedicine.medical_specialtyHistologyPeriod (gene)Pineal GlandPathology and Forensic MedicineMelatoninSynapsePineal glandInternal medicinemedicineAnimalsCircadian rhythmMelatoninLagomorphabiologyNervous tissueCell Biologybiology.organism_classificationCircadian Rhythmmedicine.anatomical_structureEndocrinologynervous systemRabbitssense organsNeuronhormones hormone substitutes and hormone antagonistsmedicine.drug

description

Previous studies have shown that pineal "synaptic" ribbons and spherules may respond differently under normal and experimental conditions. It has been suggested that the increase in the number of ribbons may be a prerequisite for enhanced melatonin formation. In the present study, the number of ribbons and spherules as well as the level of serum melatonin were monitored over a 24-h period in the male rabbit, the pineal gland of which is known to contain many spherules. It was found that both the number of ribbons and the levels of serum melatonin show the typical nocturnal increase, exhibiting peaks at 02:00 and 06:00 h, respectively. There is a good correlation (R = 0.8) of the two parameters. The spherules, in contrast, show no statistically significant circadian changes in number and cannot be correlated with the levels of serum melatonin. It is concluded that ribbons and spherules may differ in function and that the ribbons may be somehow involved in the regulation of melatonin formation.

yearjournalcountryeditionlanguage
1984-06-01Cell and Tissue Research
https://doi.org/10.1007/bf00217222