NSCI 1001 - Metabolism

Metabolism (parts 1 & 2)

Hypothalamus

Regulates vital physiological functions for homeostasis.

Homeostasis

Maintains stable internal physiological conditions.

Walter B. Cannon

Introduced the concept of homeostasis.

Physiological parameters

Variables like temperature, blood pressure, and fluid composition.

Autonomic nervous system

Regulates involuntary body processes unconsciously.

Sympathetic nervous system

Activates 'fight-or-flight' response during stress.

Parasympathetic nervous system

Responsible for 'rest-and-digest' body processes.

Enteric nervous system

Manages digestion and gastrointestinal functions.

Ganglia

Enlargements of peripheral nerves containing autonomic neurons.

Preganglionic neurons

Neurons originating in the spinal cord and brainstem.

Endocrine system

Network of glands controlling bodily functions via hormones.

Hormone

Signaling molecules regulating physiology and behavior.

Pituitary gland

Master gland regulating many bodily functions.

Negative feedback loop

Regulates hormone concentration to maintain homeostasis.

Positive feedback loop

Less common, amplifies hormone production.

Adrenaline

Hormone released during stress by sympathetic system.

Noradrenaline

Neurotransmitter involved in sympathetic nervous responses.

Acetylcholine

Neurotransmitter used by parasympathetic nervous system.

Adenohypophysis

Anterior lobe of the pituitary gland.

Neurohypophysis

Posterior lobe of the pituitary gland.

Feedback mechanism

Loop controlling production of hormones.

End-organs

Tissues innervated by sympathetic and parasympathetic systems.

Positive feedback

Increases hormone concentration over time.

Hypothalamus

Modulates emotional responses and communicates with brain areas.

Prefrontal cortex (PFC)

Involved in emotional processing and decision-making.

Amygdala

Processes emotions, especially fear and pleasure.

Hippocampus

Key for memory formation and emotional regulation.

PFC-amygdala pathway

Crucial for emotional learning and social interactions.

Nucleus Accumbens (NAc)

Involved in pleasure, motivation, and reward-seeking.

Energy balance

Regulated by the brain's response to hormones.

Orexigenic peptides

Promote food intake and reduce energy expenditure.

Anorexigenic peptides

Decrease food intake and increase energy expenditure.

Arcuate nucleus (ARC)

Main sensor for body metabolism and energy regulation.

Neuropeptide Y

Orexigenic peptide that stimulates appetite.

Proopiomelanocortin (POMC)

Anorexigenic peptide that suppresses appetite.

Glucose homeostasis

Regulated by hypothalamus and brainstem functions.

Insulin resistance

Cells fail to respond to insulin, raising blood sugar.

Central hormonal resistance

Brain's reduced response to hormones like leptin.

Leptin

Hormone regulating energy balance and appetite.

Metabolic dysregulation

Leads to obesity and type 2 diabetes.

Peripheral hormonal resistance

Tissues unresponsive to hormones, affecting metabolism.

Hepatic glucose production

Liver's role in regulating blood glucose levels.

Skeletal muscle glucose uptake

Muscle's absorption of glucose for energy.

Autonomic projections

Nuclei send signals to modulate organ functions.

Hormonal resistance

Tissues inadequately respond to hormone effects.

Leptin

Hormone from fat tissue that regulates appetite.

Obesity

Condition causing resistance to leptin signals.

Hypothalamic integration

Hormonal coordination in the hypothalamus.

Biological rhythm

Endogenous cycle persisting without external cues.

Circadian rhythm

24-hour cycle affecting physical and mental processes.

Chronobiology

Study of biological rhythms and their effects.

Suprachiasmatic nucleus (SCN)

Principal circadian clock regulating daily behavior.

Autonomous timing mechanism

SCN neurons maintain timing independently.

Circadian desynchronization

Mismatch between internal clock and environment.

Misalignment factors

Elements causing circadian rhythm disruption.

Shift work

Work schedule disrupting normal circadian rhythms.

Risk of cardiovascular disease

Increased by 40% due to circadian misalignment.

Metabolic syndrome

Cluster of conditions increasing heart disease risk.

Psychosocial factors

Social and psychological influences on circadian rhythms.

Core body temperature

Physiological measure influenced by circadian rhythms.

Neuroendocrine function

Hormonal activity regulated by circadian rhythms.

Memory performance

Cognitive function affected by circadian cycles.

Psychomotor performance

Physical response influenced by circadian timing.

Environmental cues

External signals affecting biological rhythms.

Light exposure

Key factor influencing circadian rhythms.

Seasonal photoperiods

Seasonal changes affecting biological timing.

Daily sleep-wake cycle

Typical circadian rhythm for humans.

Tidal variations

Behavioral changes in coastal animals related to tides.

Neurodegenerative diseases

Progressive disorders affecting neurons, no current cures.

Cholinesterase inhibitors

Medications preventing acetylcholine breakdown for memory.

Acetylcholine

Brain chemical crucial for memory and cognition.

Lecanemab

FDA-approved immunotherapy targeting beta-amyloid in Alzheimer's.

Donanemab

Immunotherapy drug reducing amyloid plaques in Alzheimer's.

Levodopa

Gold standard medication for Parkinson's motor symptoms.

Dopamine agonists

Medications mimicking dopamine, used in early PD stages.

Pramipexole

Dopamine agonist for Parkinson's disease treatment.

Rotigotine

Dopamine agonist available as a patch for PD.

Deep brain stimulation (DBS)

Surgical treatment using electrodes to modulate brain activity.

Amyloid plaques

Protein aggregates associated with Alzheimer's disease.

Energy homeostasis

Balance of body functions for survival and health.

Claude Bernard

Introduced concept of homeostasis in physiology.

Walter B. Cannon

Defined mechanisms maintaining physiological constancy.

Hypothalamus

Brain region regulating homeostasis and vital functions.

Autonomic nervous system

Controls involuntary bodily functions, influenced by hypothalamus.

Endocrine system

Hormonal system regulated by the hypothalamus.

Homeostasis

Stable internal environment necessary for life.

Physiological parameters

Variables like temperature and blood pressure maintained by homeostasis.

Survival functions

Essential body functions including temperature and sleep regulation.

Electrolyte composition

Balance of minerals in body fluids managed by hypothalamus.

Sleep-wake cycle

Physiological pattern regulated by the hypothalamus.

Hypothalamus

Regulates physiological parameters for survival.

Hypothalamic neurons

Receive sensory information from the body.

Sensory information

Stimuli like temperature or hormonal changes.

Regulatory neurons

Integrate information in specific hypothalamic sites.

Motor circuits

Control behaviors and physiological responses downstream.

Sympathetic nervous system

Activates fight-or-flight responses in stress.

Parasympathetic nervous system

Promotes rest-and-digest body processes.

Enteric nervous system

Manages digestion of food.

Ganglia

Enlargements of peripheral nerves housing autonomic neurons.

Preganglionic neurons

Segmentally organized in spinal cord and brainstem.