Septal unit activity and hippocampal EEG during the sleep-wakefulness cycle of the rat

Morales, Francisco R.; Roig, J.A.; Monti, J.M.; Macadar, O.; Budelli, Rubén

doi:10.1016/0031-9384(71)90206-x

Cited by 41 publications

(18 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Of particular interest to the milk ejection reflex is the activity of the septum in relation to the hippocampal electroencephalographic theta rhythm that occurs during arousal or paradoxical sleep (Green & Arduini, 1954;Petsche, Stumpf & Gogolak, 1962;Gogolak, Stumpf, Petsche & Sterc, 1968; Morales, Roig, Monti, Macadar & Budelli, 1971;McLennan & Miller, 1974). In the lactating rat, the milk ejection reflex never occurs during arousal or paradoxical sleep (Voloschin & Tramezzani, 1979;Lincoln et al 1980).…”

Section: Discussionmentioning

confidence: 99%

The role of the septum in the control of the milk ejection reflex in the rat: effects of lesions and electrical stimulation.

Lebrun¹,

Poulain²,

Theodosis³

1983

The Journal of Physiology

View full text Add to dashboard Cite

SUMMARY1. Experiments were undertaken to determine the role of the septum on the afferent control of the milk ejection reflex in lactating rats.2. Massive septal lesions were produced by passing radio-frequency current through lesioning electrodes. Intramammary pressure recordings during suckling showed no significant alterations either in the frequency of milk ejections or in their amplitude and time course. 3. Electrophysiological recordings of identified oxytocin-secreting neurones in supraoptic nuclei of septal-lesioned rats engaged in suckling showed that the pattern of background electrical activity and ofthe high frequency discharges at milk ejection were normal.4. The weight of litters from rats lesioned on the third day post-partum increased in a way parallel to that of control litters up to the fifteenth post-natal day.5. Electrical stimulation was applied bilaterally to the lateral septum in trains of long duration (20-55 min) at varying frequencies. Frequencies of 5 and 10 Hz interrupted the reflex during the period of stimulation. At 1 Hz, milk ejections were not interrupted but the intervals between successive milk ejections were significantly increased in comparison to the intervals before stimulation.6. Electrical stimulation applied to the septum in short trains of 1 or 3 min at 5 and 10 Hz significantly delayed the appearance of the subsequent milk ejection. At 1 Hz, no effect was observed.7. Septal stimulation at 1 Hz for 20 min or more did not significantly alter the electrocorticogram during the period of stimulation. Stimulation at 5 Hz for the same period of time always desynchronized the e.e.g. for several minutes after the cessation of stimulation.8. It is concluded that the septum is not essential for the onset and the maintenance of reflex milk ejections during lactation. The results suggest, however, that in the normal non-anaesthetized animal, septal activation could modulate the frequency of milk ejections.

show abstract

Section: Discussionmentioning

confidence: 99%

The role of the septum in the control of the milk ejection reflex in the rat: effects of lesions and electrical stimulation.

Lebrun¹,

Poulain²,

Theodosis³

1983

The Journal of Physiology

View full text Add to dashboard Cite

show abstract

“…Several lines of evidence indicate that the septum plays a critical role in hippocampal theta rhythm generation (Morales et al 1971;Colom and Bland 1991;Bland and Colom, 1993;Lee et al, 1994;Vinogradova, 1995;Bland et al, 1999). Furthermore, the occurrence of hippocampal theta rhythm depends on the proportion of septal neurons involved in the rhythmic process while the frequency of the theta field activity is determined by the frequency of the rhythmical "theta" bursts in septal neurons (Bland and Colom, 1993;Vinogradova, 1995;Bland et al, 1999).…”

Section: Disclosures Statementmentioning

confidence: 99%

Medial septal β-amyloid 1-40 injections alter septo-hippocampal anatomy and function

Colom¹,

Castañeda²,

Bañuelos³

et al. 2010

Neurobiology of Aging

View full text Add to dashboard Cite

Degeneration of septal neurons in Alzheimer's disease (AD) results in abnormal information processing at cortical circuits and consequent brain dysfunction. The septum modulates the activity of hippocampal and cortical circuits and is crucial to the initiation and occurrence of oscillatory activities such as the hippocampal theta rhythm. Previous studies suggest that amyloid β peptide (Aβ) accumulation may trigger degeneration in AD. This study evaluates the effects of single injections of Aβ 1-40 into the medial septum. Immunohistochemistry revealed a decrease in septal cholinergic (57%) and glutamatergic (53%) neurons in Aβ 1-40 treated tissue. Additionally, glutamatergic terminals were significantly less in Aβ treated tissue. In contrast, septal GABAergic neurons were spared. Unitary recordings from septal neurons and hippocampal field potentials revealed an approximately 50% increase in firing rates of slow firing septal neurons during theta rhythm and large irregular amplitude (LIA) hippocampal activities and a significantly reduced hippocampal theta rhythm power (49%) in Aβ 1-40 treated tissue. Aβ also markedly reduced the proportion of slow firing septal neurons correlated to the hippocampal theta rhythm by 96%. These results confirm that Aβ alters the anatomy and physiology of the medial septum contributing to septohippocampal dysfunction. The Aβ induced injury of septal cholinergic and glutamatergic networks may contribute to an altered hippocampal theta rhythm which may underlie the memory loss typically observed in AD patients.

show abstract

“…We have previously shown an interrelationship between the optic system and suprachiasmatic nuclei neurones, as well as the latter's influence on the cervical sympathetic nerves which innervate the pineal gland (Nishino, et al 1976 (Yamaoka & Hagino, 1974). Since recordings have not been taken throughout the entire day in their work, it is not known whether septal neurones possess a circadian rhythm but it is interesting that septal neurones have a close relationship to the hippocampus (Macadar, Roig, Monti & Budelli, 1970;Yokota, Reeves & MacLean, 1970;Morales, Roig, Monti, Macadar & Budelli, 1971), which is said to be involved in diurnal variation of ACTH release (Mason, 1958;Moberg, Scapagnini, de Groot & Ganong, 1971). More studies will be needed to find the source of circadian and other rhythmic fluctuations of LHA neurones.…”

Section: Discussionmentioning

confidence: 99%

Circadian and other rhythmic activity of neurones in the ventromedial nuclei and lateral hypothalamic area.

Koizumi¹,

Nishino²

1976

The Journal of Physiology

View full text Add to dashboard Cite

accelerated firing of VMN cells. This was true during the day period as well as at night when background activities of VMN and LHA neurones were different from that of the day.7. Stimulation of the septal area with subthreshold pulses at a low rate (1-0 3fsec) suppressed or altered oscillations in firing frequency of LHA neurones. Severance of connexion between LHA and structures caudal thereto had no effect on LHA neurone firing rates or rhythms.Sections between the septal area and LHA, however, abolished or greatly altered the oscillatory rhythms of LHIA cell activity, although spontaneous discharges continued at a somewhat lower rate for periods of hours.8. Stimulation of suprachiasmatic nuclei with weak intensity and low frequency also changed oscillatory fluctuations in firing of LILA neurones.9. Possible origins of circadian rhythm and oscillations of short duration in firing pattern of VMN and LHA neurones were discussed.

show abstract

Septal unit activity and hippocampal EEG during the sleep-wakefulness cycle of the rat

Cited by 41 publications

References 5 publications

The role of the septum in the control of the milk ejection reflex in the rat: effects of lesions and electrical stimulation.

The role of the septum in the control of the milk ejection reflex in the rat: effects of lesions and electrical stimulation.

Medial septal β-amyloid 1-40 injections alter septo-hippocampal anatomy and function

Circadian and other rhythmic activity of neurones in the ventromedial nuclei and lateral hypothalamic area.

Contact Info

Product

Resources

About