Vasoactive Intestinal Peptides (VIP)
Vasoactive Intestinal Peptides (VIP)
Key Points
- 28-amino acid peptide hormone
- Member of secretin/glucagon family
- Major neurotransmitter in brain and gut
- Critical role in development and homeostasis
Introduction
Vasoactive Intestinal Peptide (VIP) is a multifunctional neuropeptide with crucial roles in neurodevelopment, immune response, and gastrointestinal function. In pediatric medicine, understanding VIP is essential for managing various developmental, gastrointestinal, and neurological conditions.
Structure and Synthesis
Molecular Characteristics
- Structure
- 28 amino acid polypeptide
- Highly conserved across species
- Similar to secretin and glucagon
- Synthesis
- Derived from 170-amino acid prepro-VIP
- Post-translational processing
- Storage in secretory granules
Distribution
- Central Nervous System
- Cerebral cortex
- Hypothalamus
- Pituitary gland
- Peripheral Tissues
- Gastrointestinal tract
- Respiratory system
- Pancreas
Physiological Actions
Receptor System
- VPAC1 Receptor
- Distribution in brain and periphery
- G-protein coupled mechanism
- cAMP-dependent signaling
- VPAC2 Receptor
- Smooth muscle expression
- Immune cell presence
- Role in circadian rhythm
Major Functions
- Gastrointestinal Effects
- Smooth muscle relaxation
- Secretion stimulation
- Blood flow regulation
- Intestinal barrier protection
- Neuroendocrine Functions
- Circadian rhythm regulation
- Growth hormone release
- Prolactin secretion
- Immunological Role
- Anti-inflammatory actions
- T-cell regulation
- Cytokine modulation
Clinical Applications
Therapeutic Uses
- Pulmonary Disorders
- Bronchodilation
- Pulmonary hypertension
- Asthma management
- Gastrointestinal Conditions
- Secretory diarrhea
- Inflammatory bowel disease
- Intestinal motility disorders
- Neurological Applications
- Neurodevelopmental disorders
- Neuroprotection
- Pain management
Diagnostic Applications
- VIP-secreting tumors
- Endocrine disorders
- Inflammatory conditions
VIP-Related Disorders
VIPomas
- Clinical Presentation
- Watery diarrhea
- Hypokalemia
- Achlorhydria
- Metabolic acidosis
- Diagnosis
- VIP level measurement
- Imaging studies
- Endoscopic evaluation
- Management
- Somatostatin analogs
- Surgical resection
- Supportive care
VIP Deficiency States
- Manifestations
- Bronchial hyperreactivity
- Inflammatory conditions
- Circadian rhythm disturbances
- Treatment Approaches
- VIP replacement therapy
- Symptom management
- Preventive measures
Monitoring and Management
- Laboratory Parameters
- Serum VIP levels
- Electrolyte balance
- Acid-base status
- Clinical Monitoring
- Growth parameters
- Developmental milestones
- Gastrointestinal function
