Neurotransmitters are involved in the transmission of impulses at the chemical synapses. They are present in the synaptic vesicles at the axon terminals.
Hormones are non-nutrient chemicals which act as intercellular messengers produced in trace amounts.
Cerebrospinal fluid is present in the subarachnoid space. It provideds shock resistance to brain.
Lymph is a colourless fluid containing specialised lymphocytes which are responsible for the immune responses of the body. It is an important carrier of nutrients, hormones, etc. Fats are absorbed through lacteals (lymph vessels) present in microvilli of intestine.