What does rat saliva contain?

What does rat saliva contain? - briefly

Rat saliva contains enzymes (e.g., amylase, proteases), antimicrobial peptides such as defensins, a range of proteins, hormones, electrolytes (Na⁺, K⁺, Cl⁻) and trace minerals. These substances support digestion, oral hygiene and resistance to pathogens.

What does rat saliva contain? - in detail

Rat saliva is a complex fluid whose primary constituent is water, accounting for roughly 95 % of its volume. The remaining fraction comprises a mixture of inorganic ions, organic molecules, and bioactive proteins that support digestion, immunity, and social communication.

Inorganic components

  • Sodium (Na⁺) and potassium (K⁺) – maintain osmotic balance and nerve function.
  • Chloride (Cl⁻) and bicarbonate (HCO₃⁻) – buffer pH.
  • Calcium (Ca²⁺) and magnesium (Mg²⁺) – co‑factor for enzymatic activity.

Organic constituents

  • Carbohydrates: small amounts of glucose and maltose, products of oral starch breakdown.
  • Lipids: trace phospholipids and fatty acids derived from diet and glandular secretions.

Proteins and enzymes

  • Amylase – initiates starch hydrolysis.
  • Lysozyme – bacteriolytic activity targeting Gram‑positive cell walls.
  • Kallikrein‑related peptidases – modulate blood pressure and inflammation.
  • Proteases (e.g., trypsin‑like enzymes) – degrade protein substrates.
  • Mucins – high‑molecular‑weight glycoproteins that increase viscosity, protect mucosal surfaces, and facilitate grooming.
  • Immunoglobulin A (IgA) – provides mucosal immunity by neutralizing pathogens.
  • Antimicrobial peptides (e.g., defensins) – broad‑spectrum microbicidal agents.
  • Growth factors (e.g., epidermal growth factor) – promote epithelial repair.

Chemical signals

  • Volatile organic compounds and pheromonal proteins – convey territorial and reproductive information during grooming and marking behaviors.
  • Small metabolites (e.g., uric acid) – contribute to scent profile.

Microbial content

  • Commensal bacteria, predominantly Lactobacillus and Streptococcus species, inhabit the oral cavity and are present in saliva; they participate in maintaining a balanced oral microbiome.

The quantitative profile varies with age, diet, health status, and environmental conditions, but the described constituents consistently define the functional properties of rat saliva.