Research Laboratories

Sleep Laboratory
Incharge- Prof. H.N. Mallick

The Department of Physiology at All India Institute of Medical Sciences has some of the best laboratories in this continent working on neurophysiology of sleep. One of the sleep laboratories is named after late Dr. Baldev Singh, who, as an emeritus professor of AIIMS, was instrumental in encouraging sleep medicine in this country. Another one is named after the founder of this department B.K.Anand, as a mark of respect to his scientific contribution in the understanding of hypothalamic functions.

The laboratories have got excellent telemetry set up for recording EOG, EEG, EMG and body temperature and activity monitoring system to assess thermal preference of the animalsThere are two specially fabricated environmental chambers to study the thermal preference of the animals. No other laboratory in the world can boast of such a facility. In addition to the classical polygraphs for sleep recording, it is also equipped with systems for digital polysomnography. A separate unit is devoted to the electrophysiological analysis of central neurons. This lab has every apparatus necessary for unit recording and iontophoretic studies. DST, DRDO, DBT, ICMR and CSIR primarily supported the research.

A holistic approach, with simultaneous monitoring of sleep-wakefulness, thermoregulation and reproductive functions, have helped this department establish the key role played by the preoptic area in the regulation of sleep-wakefulness. The major achievements of the group can be listed as follows:

The studies conducted by the department provided convincing evidence to show that the medial preoptic neurons form the most important part of the neural circuitry, which regulates sleep.

Sleep laboratory studied the role of the noradrenergic afferent fibres, projecting to the preoptic area, in the regulation of several visceral functions, including sleep. This research group was the first to show the involvement of these noradrenergic fibres in the induction of sleep.

This laboratory was also a pioneer in demonstrating the restoration of functions after neural tissue transplantation. They were the first to show recovery of sleep after neural transplantation at the medial preoptic area. Electrophysiological recordings from the transplant were a significant scientific contribution.

Magnetic resonance imaging of the lesioned preoptic area, done with the help of NMR facility, was a rare achievement for which this country can be proud. By employing fMRI, this group was the first to demonstrate the activation of the medial preoptic neurons during sleep.

The studies conducted by the laboratory showed that the medial preoptic area has the homeostatic mechanism for fine-tuning food intake, body temperature, locomotor activity and sleep-wakefulness.

Recent Publications

1. Vetrivelan R, Mallick HN, Kumar VM. Tonic activity of a₁ adrenergic receptors of the medial preoptic area contributes towards increased sleep in rats. Neuroscience. 2006; 139 (3): 1141-1151.

2. Srividya R, Mallick HN, Kumar VM. The effect of NMDA lesion of the medial preoptic area and the lateral preoptic area in thermoregulation and sleep -wakefulness in rats. Neuroscience. 2006; 139(3): 853-864.

3. Vetrivelan R, Mallick HN, Kumar VM. Sleep induction and temperature lowering by medial preoptic α₁ adrenergic receptors. Physiol Behav. 2006; 87(4): 707-713.

4. K K Gulia, KK, Mallick HN, Kumar VM. Sleep and sexual behavior: A cross talk. In: 2nd Interim Congress of the World Federation of Sleep Research and Medicine Societies -WFSRSMS, Eds Kumar VM, Mallick HN. Monduzzi Editore International Proceedings Division, Bologna, Italy. 2005; p 7-15.

5. Mahapatra AP, Mallick HN, Kumar VM. Sleep changes during chronic cold exposure showed that the homeostatic requirement of sleep is reduced in the medial preoptic area lesioned rats. Indian J Physiol Pharmacol. 2005; 49(4): 411-421.

6. Srividya R, Mallick HN, Kumar VM. The changes in thermal preference, sleep-wakefulness, body temperature and locomotor activity in the rats with medial septal lesion. Behav Brain Res. 2005 Nov 7;164(2):147-55.

7. Mallick HN, Kumar VM. Gating of dorsal penile nerve inputs by norepinephrine at the medial preoptic area in rats. Indian J Physiol Pharmacol. 2005 Jan;49(3):325-330.

8. Srividya R, Mallick HN, Kumar VM. Changes in brain temperature and thermoregulation produced by destruction of medial septal neurons in rats. Brain Res Bull. 2005 Jul 30;66(2):143-8.

9. Gulia KK, Mallick HN, Kumar VM. Ambient temperature related sleep changes in rats neonatally treated with capsaicin. Physiol Behav. 2005 Jul 21;85(4):414-8.

10. Khubchandani M, Jagannathan NR, Mallick HN, Mohan Kumar V. Functional MRI shows activation of the medial preoptic area during sleep. Neuroimage. 2005 May 15;26(1):29-35.

11. Vetrivelan R, Mallick HN, Kumar VM. Unmasking of alpha1 adrenoceptor induced hypnogenic response from medial preoptic area. Physiol Behav. 2005 Mar 31;84(4):641-50.

12. Mahapatra AP, Mallick HN, Kumar VM. Changes in sleep on chronic exposure to warm and cold ambient temperatures. Physiol Behav. 2005 Feb 15;84(2):287-94.

13. Ray B, Mallick HN, Kumar VM. Changes in sleep-wakefulness in the medial preoptic area lesioned rats: role of thermal preference. Behav Brain Res. 2005 Mar 7;158(1):43-52. Epub 2005 Jan 7.

14. Kumar VM. Body temperature and sleep: Are they controlled by the same mechanism? Sleep and Biological Rhythms. 2005; 2: 103-124,.

14. Gulia KK, Mallick HN, Kumar VM. Atenolol or butoxamine injection at the lateral septum doesn't inhibit male sexual behavior in rats.
Indian J Physiol Pharmacol. 2005 Jan;49(1):103-7.

15. Gulia KK, Mallick HN, Kumar VM. Sleep-related penile erections do not occur in rats during carbachol-induced rapid eye movement sleep.
Behav Brain Res. 2004 Oct 5;154(2):585-7.

16. Ray B, Mallick HN, Kumar VM. Changes in thermal preference, sleep-wakefulness, body temperature and locomotor activity of rats during continuous recording for 24 hours. Behav Brain Res. 2004 Oct 5;154(2):519-26.

17. Vetrivelan R, Mallick HN, Kumar VM. Repeated intracerebral microinjections: efficacy in studying brain functions. Indian J Physiol Pharmacol. 2004 Oct;48(4):471-5.

18. Srividya R, Mallick HN, Kumar VM. Sleep changes produced by destruction of medial septal neurons in rats. Neuroreport. 2004 Aug 6;15(11):1831-5.

19. Kumar VM. Why the medial preoptic area is important for sleep regulation.
Indian J Physiol Pharmacol. 2004 Apr; 48(2): 137-49. Review.

20. Kumar VM. Role of noradrenergic fibers of the preoptic area in regulating sleep. J Chem Neuroanat. 2003 Oct;26(2):87-93.

21. Kumar VM. Interrelation between thermoregulation and sleep regulation. Proc Indian Nat Sci Acad. 69: 418-435, 2003.

22. Khubchandani M, Mallick HN, Jagannathan NR, Mohan Kumar V. Stereotaxic assembly and procedures for simultaneous electrophysiological and MRI study of conscious rat. Magn Reson Med. 2003
May;49(5):962-7.

 

24. Vetrivelan R, Mallick HN, Kumar VM. Changes in body temperature and sleep-wakefulness after intrapreoptic injection of methoxamine in rats.
Neural Plast. 2003;10(4):267-78.

25. Gulia KK, Mallick HN, Kumar VM. Orexin A (hypocretin-1) application at the medial preoptic area potentiates male sexual behavior in rats.
Neuroscience. 2003;116(4):921-3.