Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Videos

Preweanling rats: recovery from lateral hypothalamic damage

C R Almli, G T Golden

    Journal of Comparative and Physiological Psychology
    |November 1, 1976
    PubMed
    Summary

    This study examines how young rats recover after damage to the lateral hypothalamus, a brain region involved in hunger and thirst. Researchers found that while these animals eventually regain the ability to eat and drink on their own, they retain long-term difficulties in responding to specific hydration and metabolic stresses. The findings suggest that the brain's ability to compensate for this injury is similar regardless of whether the damage occurs early in life or during adulthood.

    Related Concept Videos

    You might also read

    Related Articles

    Articles linked to this work by shared authors, journal, and citation graph.

    Sort by
    Same author

    The NIH MRI study of normal brain development (Objective-2): newborns, infants, toddlers, and preschoolers.

    NeuroImage·2007
    Same author

    Association between variation in the human KCNJ10 potassium ion channel gene and seizure susceptibility.

    Epilepsy research·2004
    Same author

    A prospective, longitudinal diffusion tensor imaging study of brain injury in newborns.

    Neurology·2002
    Same author

    Normal brain maturation during childhood: developmental trends characterized with diffusion-tensor MR imaging.

    Radiology·2001
    Same author

    Quantitative genetic study of maximal electroshock seizure threshold in mice: evidence for a major seizure susceptibility locus on distal chromosome 1.

    Genomics·2001
    Same author

    Human fetal and neonatal movement patterns: Gender differences and fetal-to-neonatal continuity.

    Developmental psychobiology·2001

    Area of Science:

    • Developmental neuroscience and lateral hypothalamic area research
    • Behavioral physiology within mammalian biology

    Background:

    No prior work had resolved whether early-life brain injury allows for complete functional restoration. That uncertainty drove researchers to examine the lateral hypothalamus, a region known for regulating basic survival behaviors. It was already known that adult animals exhibit a specific recovery syndrome after such damage. This gap motivated an investigation into whether preweanling subjects follow a similar trajectory. Prior research has shown that developmental plasticity might offer unique compensatory mechanisms. However, the extent of long-term behavioral deficits in these young subjects remained unclear. Scientists needed to determine if early damage leads to permanent physiological consequences. This study addresses the long-term impact of hypothalamic destruction during the preweanling period.

    Purpose Of The Study:

    The study aims to determine if early-life damage to the lateral hypothalamic area allows for functional restoration. Researchers sought to compare the recovery patterns of young subjects against established adult models. They investigated whether bilateral or unilateral destruction leads to different long-term behavioral outcomes. The team focused on identifying permanent deficits in feeding and drinking regulation. They intended to clarify if developmental plasticity influences the severity of the recovery syndrome. The researchers also aimed to document sex-related differences in body weight maintenance after the injury. This work addresses the uncertainty regarding whether the brain can fully compensate for such damage during early development. The motivation was to establish if the timing of the lesion alters the fundamental physiological consequences observed in mature animals.

    Keywords:
    hypothalamic recovery syndromedevelopmental neurobiologyhomeostatic regulationmetabolic deficits

    Frequently Asked Questions

    The researchers propose that subjects regain voluntary feeding and drinking behaviors between 44 and 75 days of age following bilateral destruction. This recovery process is termed the lateral hypothalamic recovery syndrome, which characterizes the return of basic survival functions despite the initial injury.

    The authors utilize 2-deoxy-D-glucose to test metabolic responsiveness. This chemical agent induces a state of glucoprivation, allowing the team to measure whether the subjects can initiate feeding in response to internal energy deficits, which they ultimately failed to do.

    Bilateral destruction is necessary to observe the full lateral hypothalamic recovery syndrome, whereas unilateral damage results in a shorter recovery timeline. The researchers note that unilateral subjects regain feeding and drinking abilities significantly faster, specifically between 25 and 32 days of age.

    Related Experiment Videos

    Main Methods:

    The investigators performed surgical destruction of the target brain region in ten-day-old albino subjects. They utilized both bilateral and unilateral approaches to evaluate the extent of functional impairment. The team monitored the animals throughout their development to track the return of voluntary intake. They implemented specific metabolic and hydrational challenges to test homeostatic regulation in the maturing subjects. Researchers recorded daily body mass to compare growth trajectories between the sexes. They maintained the animals until they reached adulthood to observe long-term behavioral consequences. The experimental design allowed for a direct comparison between early-life and adult injury models. This systematic observation provided a comprehensive view of the recovery process over several months.

    Main Results:

    The researchers observed that bilateral subjects regained voluntary feeding and drinking between 44 and 75 days of age. These animals exhibited permanent deficits in responding to hydrational challenges through 275 days of age. The subjects failed to initiate feeding following 2-deoxy-D-glucose treatment, indicating a lasting metabolic impairment. Male subjects experienced a permanent 20% to 25% depression in body weight. Female subjects displayed only a temporary reduction in body mass during the recovery period. Unilateral subjects recovered voluntary feeding and drinking much faster, specifically by 32 days of age. These unilateral animals also showed persistent difficulties with hydrational regulation. The investigation demonstrated that the consequences of the damage were nearly identical to those seen in adult models.

    Conclusions:

    The authors propose that early-life damage to this brain region results in outcomes comparable to adult injury. Their findings indicate that voluntary intake of nutrients and liquids eventually returns in these subjects. The researchers suggest that permanent impairments persist regarding specific hydrational and metabolic challenges. They observe that sex-based differences influence long-term body weight regulation following these lesions. The team concludes that the recovery syndrome manifests similarly across different stages of development. Their data highlight that early intervention does not prevent all lasting physiological deficits. The study implies that the brain possesses limited capacity to fully overcome these specific hypothalamic injuries. These observations suggest that the fundamental behavioral consequences of such damage remain stable throughout the lifespan.

    The team employs body weight data to evaluate long-term physiological regulation. This metric reveals that male subjects experience a permanent 20% to 25% reduction in mass, while female subjects show only a temporary decrease, highlighting a distinct sex-based difference in recovery.

    The researchers measure responses to hydrational challenges to assess long-term functional deficits. They report that both unilateral and bilateral groups display permanent impairments in these specific regulatory tasks, indicating that certain homeostatic mechanisms do not recover even after voluntary feeding returns.

    The authors propose that the effects of this brain damage are nearly identical regardless of the age at which the injury occurs. This implication suggests that the developmental stage does not fundamentally alter the long-term behavioral outcomes associated with this specific hypothalamic destruction.